Sticky Tape Mystery

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Sticky Tape Mystery

Post by Ciaolo on Thu Jan 12, 2017 12:52 pm

You would never believe what this article is about!

Enjoy the many 'unexpected', 'mysterious' and 'unexplained' stuff they discover.

http://www.nature.com/news/2008/081022/full/news.2008.1185.html

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Re: Sticky Tape Mystery

Post by LongtimeAirman on Thu Jan 12, 2017 3:54 pm

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Thanks Ciaolo. With all my tapping the pi=4 tracks and Christmas packages I realize I probably don’t have long to live. I’ll quickly add to the list.

1) The nature video.
https://www.youtube.com/watch?v=r63e5y3Z3R8
Sticky tape X-Ray
length 0:08:36
0:00:23/0:08:36 Referencing: Sticky Tape X-rays, Nature, Vol 455, Issue 7216, 23 October 2008.
X-rays at 50,000V are created by unrolling so-called ordinary “scotch tape”. Note that the Nature article was careful to add that x-rays from tape was found when conducting the experiment in vacuum and not in air. Russia 1930s Abramov suggested there were bursts of energy from splitting mica, or 1950s Karasev (?) suggested pulling tape could produce x-rays. The main cause is due to mechanical force separating charges - like the Van deGraf generator. Creation of an x-ray image, cheap(!) X-ray device.
5:58/8:36 Gooey interface separation with microscope. Radiation centered on the vertex of peeling tape (unrolling at about 5cm/sec), about 100microns long, producing 100,000 x-ray photos every billionth of a second (10-9). They feel they could improve the x-ray production 10-100x by selecting improved adhesives. Sure enough, they observed a 10x improvement by changing to a different brand tape.

2) A technical paper with details and plenty of math.
http://www.nanoqed.org/resources/Triboluminescence.pdf
Triboluminescence and X-Rays
T.V. Prevenslik
tribology@nanoqed.net

For the record, I passed all my exams but that doesn’t necessarily mean I understood any or all of it. I need to work on my math skills just like most people. Or logic, and precision too, constant attention and effort is necessary in order to improve. On the other hand, Miles has shown that the easiest way mainstream misdirects people is through the math, overemphasis on the wrong maths usually boils down to a waste of time. Judgement is required. I've been wrong many times.

We’ve touched on the subject of static electricity here on this site. The mainstream sees charge separation followed by charge equalization. I believe Miles would agree that peeling tape causes electrons to be stripped from the tape’s adhesive causing ionization. Without electrons present (and in their proper locations) charge flow both to and from the adhesive is greatly increased. That ionization is lost when electrons and positrons finally position themselves limiting the adhesive’s atomic photon inrush currents.

P.S. It just occurred to me that stripping electrons away from the adhesive's surface is wrong. I imagine it now as a continuous sheet of adhesive, which is essentially torn apart, exposing surface that has never been exposed to the outside. Within that 100 or so microns (5cm/sec), the exposed atoms pass large two-way currents from which new electrons and positrons will eventually clog and diminish the charge current. Until they do, the specific production of relatively 50KV (low energy) x-rays is of course very interesting.
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Last edited by LongtimeAirman on Thu Jan 12, 2017 11:33 pm; edited 3 times in total (Reason for editing : Corrected typos, url, added 5cm/sec ... Added PS)

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Static Electricity

Post by LongtimeAirman on Thu Jan 12, 2017 11:11 pm

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Cr6, I hope you don't mind me reposting you.

/////////////////////////////////////////////////////////////////

Re: Static Electricity Defies Simple Explanation
http://www.thunderbolts.info/forum/phpBB3/viewtopic.php?f=10&t=15057#p96169
by Chromium6 » Tue May 27, 2014 8:28 pm
Found these experiments:
------

Antioxidants dispel static electricity

Cheap coating helps electric charge to dissipate from plastics and rubber.

Richard Van Noorden

19 September 2013

It might be called a shock finding. Coating plastic or rubber materials with antioxidants such as vitamin E stops static charge from building up on the polymer’s surface, chemists report today1. The discovery could prove a cheap solution to problems such as dust clinging to plastic, static electric shocks, or the sparks that damage television circuits and fry computer motherboards.

Children can have fun with static electricity — when they rub balloons on their hair, the rubber and hair stick together because of the attraction between transferred charged particles. But static charge that builds up on industrial components, such as plastic fuel filters on cars or inside semiconductor parts, can lead to potentially dangerous electric sparks and a build-up of dust.

The puzzle with static electricity, explains Bartosz Grzybowski, a physical chemist at Northwestern University in Evanston, Illinois, is that although charged particles should repel each other when they land on an insulating surface, making them spread evenly across a material and leak back into the air, they actually form stable, long-lived clumps. This leads to the build-up of large amounts of tightly confined static charge, enough to abruptly discharge when a conductive path becomes available: for example, shooting through a human body to a metal railing, or sparking through air like a miniature lightning bolt.
Vitamin treatment

Grzybowski’s team reports in Science that it has solved the mystery. The researchers examined under the microscope the patterns of electric and magnetic charge created when charged particles land on polymer surfaces. They discovered that charged particles are stabilized by radicals — reactive molecules with spare, unbound electrons that form when chemical bonds are broken on a surface. The radicals share some of the burden of the electric charge; without them, charged particles would not be able to clump together so tightly. The answer, the team says, is to apply surface coatings that react chemically with the radicals, mopping them up. Such coatings could include vitamin E, among other cheap, non-toxic antioxidants. Some of these chemicals are in fact already added to the blends from which polymers are made, in order to scavenge the radicals formed when ultra-violet light damages plastic - but haven't been used as antistatic coatings.

The researchers proved their case by using solutions of radical scavengers to coat common polymers, such as beads of polystyrene. Sure enough, after being shaken up to gain static charge, the coated beads shed their static electricity within minutes. The scientists also used their anti-static coating to protect a transistor component, showing that it remained undamaged when charged particles were shot at it from an ion gun. “It’s actually quite incredible that the answer is so simple,” says Grzybowski.

Other researchers contacted by Nature found the work exciting. The real advance is the insight into the root causes of static electricity, says Michael Dickey, who researches nano-electronics at North Carolina State University in Raleigh. “It is very clever in the simplicity of addressing an old problem,” he adds.

Dealing with the effects of static electricity is "a very big problem in industry,” says Fred Roska, a researcher at 3M in Saint Paul, Minnesota. He adds that simply finding ways to supply charged particles that neutralize the static charge building up on polymers during semiconductor manufacturing, for example, is a billion dollar market. Industrial firms also deal with static electricity by modifying the materials they use: either by covering polymers with water or gel coatings through which charge can dissipate, or by inserting conductive strips of metal or carbon nanotube into a polymer blend to provide a path for static charge to fade away.

But those solutions involve trade-offs, Grzybowski says, such as making a plastic more conductive, and do not address the underlying cause of the static build-up. And he thinks that the antioxidant coatings will prove a cheaper solution. He says that he has patented the discovery and hopes to license it to companies such as 3M and Dow.

Nature
doi:10.1038/nature.2013.13786

References

Baytekin, H. T., Baytekin, B., Hermans, T. M., Kowalczyk, B. & Grzybowski, B. A. Science 341, 1368–1371 (2013).
http://www.nature.com/news/antioxidants ... ty-1.13786

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https://www.sciencemag.org/content/333/6040/308

The Mosaic of Surface Charge in Contact Electrification

H. T. Baytekin,
A. Z. Patashinski,
M. Branicki,
B. Baytekin,
S. Soh,
B. A. Grzybowski*

Department of Chemistry and Department of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA.

E-mail: grzybor{at}northwestern.edu

Abstract

When dielectric materials are brought into contact and then separated, they develop static electricity. For centuries, it has been assumed that such contact charging derives from the spatially homogeneous material properties (along the material’s surface) and that within a given pair of materials, one charges uniformly positively and the other negatively. We demonstrate that this picture of contact charging is incorrect. Whereas each contact-electrified piece develops a net charge of either positive or negative polarity, each surface supports a random “mosaic” of oppositely charged regions of nanoscopic dimensions. These mosaics of surface charge have the same topological characteristics for different types of electrified dielectrics and accommodate significantly more charge per unit area than previously thought.

----


A Shocking New Understanding of Static Electricity

A new study has found that the age-old understanding of this everyday phenomenon—one item becoming positively charged while the other becomes uniformly negative—is incorrect.


Grzybowski admits it's bizarre to find a huge surprise in a topic that has been studied since Greek polymath Thales of Miletus first rubbed amber on wool in 600 B.C., and found it could then attract light objects like feathers. Leading lights such as Nikola Tesla and Michael Faraday have studied the phenomenon, but they too reached the same conclusion. "One assumption common to all these models is that one material was positively charged, and one negatively charged," Grzybowski says. "This is actually not true."

Perhaps we shouldn't be too surprised: Static electricity is a weird phenomenon to begin with, arising from contact between two insulators—materials that don't conduct electricity, but can create it when rubbed together. To test it in the lab, Grzybowski and colleagues used not balloons, but materials like the common polymers PDMS and Teflon. He pressed samples of insulators together before separating them (rubbing them could create more electrification but would make results harder to analyze). He then used Kelvin probe microscopy to measure molecular charges in the material. With this technique, a scientist runs a tiny probe over the microscopic hills and valleys of surfaces, and the probe vibrates differently over differently charged regions, creating a map of the charges. That's how Grzybowski saw that each material had a random patchwork of positive and negative charges, and neither was uniformly charged. In addition, his tests showed that PDMS and Teflon exchange silicon and fluorine atoms upon contact, a more significant transfer of material than ever previously shown.

Case Western Reserve University chemical engineer Daniel Lacks says this new understanding is both fascinating and surprisingly practical. For instance, photocopying depends on precisely delivering charges to ink particles so they end up in the right place on the paper. But Lacks recalls several examples of powders becoming unexpectedly charged and exploding during manufacturing, something engineers could hopefully avoid with better knowledge of static electricity. That knowledge could also lead to better industrial coatings, which would help people like the manufacturer of polyethylene that Lacks advises. During the creation of polyethylene, sometimes the particles get unexpectedly charged and stick to the side of the reactor vessel. "Then you have to shut it down and clear out the chunks with chainsaws and blowtorches," he says.

Grzybowski's new study also provides new puzzles for scientists to investigate. While the new study overturns some older beliefs about static electricity, it doesn't fully explain how the phenomenon works. "It's a great day when you come to the office and somebody shows you that your beliefs are wrong," UCLA physicist Seth Putterman says.

Putterman says one thing that remains unexplained after this new study—and surprises him—is that the geometry of the charge pattern (that map of the different charges) doesn't change significantly as the two statically charged object move together and the charge decreases. To him, this implies that ions that move around easily on an object's surface are not causing static electricity. If they were, they should change the charging pattern that Grzybowski's team saw on the surface, he says. "To me this means you have extra electrons trapped deep inside the material causing the [static electricity], and they can't go walking around the surface as would ions," he says. That's because the electrons are bound up inside the material.

Whatever the explanation proves to be, Harvard University chemist Logan McCarty says it's incredible something so common as static electricity remains such a mystery. "It's certainly more complicated than we have naively believed for many years."

http://www.popularmechanics.com/technol ... lectricity
On the Windhexe: ''An engineer could not have invented this,'' Winsness says. ''As an engineer, you don't try anything that's theoretically impossible.''
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Static Electricity

Post by LongtimeAirman on Fri Jan 13, 2017 12:29 am

.

Another Cr6 post later on the same thread.

/////////////////////////////////////////////////////////////////
Re: Static Electricity Defies Simple Explanation
http://www.thunderbolts.info/forum/phpBB3/viewtopic.php?f=10&t=15057&start=30#p98872
by Chromium6 » Fri Aug 22, 2014 9:27 pm
Static's secret rests with material exchange

27 March 2012

The charge that develops when two materials are rubbed together is dependent on tiny fragments of the materials transferring onto each other, say US scientists. The effect can even invert the normal polarity of the charging, so materials that would normally become positively charged can turn negative and vice versa.

Contact charging has provided hours of entertainment with balloons, hair and synthetic fibre clothing for generations. But it has also provided something of a headache for chemists attempting to rank materials into a 'triboelectric series' relating their propensity to develop charge. As Bartosz Grzybowski from Northwestern University in Illinois explains, looking through the literature turns up a surprising number of irreproducible and contradictory results - even for the same pairs of materials.

Over the past few years, says Grzybowski, it has become increasingly clear that contact charging is much more related to the surface properties of an object than the bulk material from which it is made. While there is still debate over what carries charge between materials - whether it is electrons, ions or both - it has also emerged that nanoscale fragments of material are transferred from each material to the other, carrying their own charge with them.

Static charge
US researchers have discovered that the transfer of nanoscale fragments of material can reverse the overall polarity of the materials

© Wiley

'People had thought that this material transfer was probably only modifying charging to a small degree,' says Grzybowski. 'We've shown that, actually, through material transfer you can change the overall polarity of the materials. So something that initially is charging minus, if you touch it a little bit more [with the charging material], it will become plus.'

'This really shows that there are at least two important mechanisms involved, and material transfer can't be ignored,' says Dan Lacks, who researches contact charging at Case Western Reserve University in Cleveland, US. 'The bad thing is it's hard to control or predict how much it's going to happen,' he adds. 'In real life you're often not starting with clean materials so you don't know what they've touched or rubbed on.'

But it goes even further than that, says Grzybowski. Even the way the polymers are processed can affect how they charge. 'At one point we were studying Teflon beads from two different suppliers, and they turned out to behave totally differently,' he says. His team have some preliminary results showing that the orientation and arrangement of the polymer chains is strongly affected by any surface charge on the mould they are made in.

It has taken a barrage of high-end analytical techniques to pin down these complexities. Grzybowski's team used a combination of various kinds of atomic force and Kelvin probe microscopy, along with Raman and x-ray photoelectron spectroscopy, plus techniques to characterise the hardness and wear parameters of the different materials.

Grzybowski attributes these latest insights to a combination of new technology to examine the phenomenon at the nanoscale, and a little of the wisdom that comes with age. 'I did similar experiments 10 years ago with George Whitesides [at Harvard University, US]. Back then we agreed it was a nightmare and we should quit, because there was nothing we could correlate with anything else!'

Lacks agrees that while new techniques have played their role in recent developments, it is an influx of new ideas that has reinvigorated interest in tribocharging. 'Once new ideas come out, it motivates more people to test things,' he says.

Phillip Broadwith



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References
H T Baytekin et al, Angew. Chem., Int. Ed., 2012, DOI:10.1002/anie.201200057

http://www.rsc.org/chemistryworld/News/ ... ansfer.asp

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Material Transfer and Polarity Reversal in Contact Charging
Angewandte Chemie Int. Ed.

Dr. H. Tarik Baytekin, Dr. Bilge Baytekin, Jared T. Incorvati, Prof. Dr. Bartosz A. Grzybowski*

The outcome of contact electrification between dielectrics depends not only on the transfer of charge but also on the transfer of material. Although only minute quantities of materials are being exchanged during contact, they can reverse the polarity of dielectrics. The reported results corroborate the mosaic model and suggest that the observations are because of the mechanical softness/hardness of the materials.

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The Mosaic of Surface Charge in Contact Electrification
Science

H. Tarik Baytekin, Alexander Z. Patashinski, Michal Branicki, Bilge Baytekin, Siowling Soh, Bartosz A. Grzybowski

When dielectric materials are brought into contact and then separated, they develop static electricity. For centuries, it has been assumed that such contact charging derives from the spatially homogeneous material properties (along the material’s surface) and that within a given pair of materials, one charges uniformly positively and the other negatively. We demonstrate that this picture of contact charging is incorrect. Whereas each contact-electrified piece develops a net charge of either positive or negative polarity, each surface supports a random “mosaic” of oppositely charged regions of nanoscopic dimensions. These mosaics of surface charge have the same topological characteristics for different types of electrified dielectrics and accommodate significantly more charge per unit area than previously thought.

http://www.sciencemag.org/content/333/6040/308.full

----------

What You Learned About Static Electricity Is Wrong

By Ars Technica
06.25.11 |
By John Timmer, Ars Technica

For many of us, static electricity is one of the earliest encounters we have with electromagnetism, and it’s a staple of high school physics. Typically, it’s explained as a product of electrons transferred in one direction between unlike substances, like glass and wool, or a balloon and a cotton T-shirt (depending on whether the demo is in a high school class or a kids’ party). Different substances have a tendency to pick up either positive or negative charges, we’re often told, and the process doesn’t transfer a lot of charge, but it’s enough to cause a balloon to stick to the ceiling, or to give someone a shock on a cold, dry day.

Nearly all of that is wrong, according to a paper published in today’s issue of Science. Charges can be transferred between identical materials, all materials behave roughly the same, the charges are the product of chemical reactions, and each surface becomes a patchwork of positive and negative charges, which reach levels a thousand times higher than the surfaces’ average charge.

Where to begin? The authors start about 2,500 years ago, noting that the study of static began with a Greek named Thales of Miletus, who generated it using amber and wool. But it wasn’t until last year that some of the authors of the new paper published a surprising result: contact electrification (as this phenomenon is known among its technically oriented fans) can occur between two sheets of the same substance, even when they’re simply allowed to lie flat against each other. “According to the conventional view of contact electrification,” they note, “this should not happen since the chemical potentials of the two surfaces/materials are identical and there is apparently no thermodynamic force to drive charge transfer.”

One possible explanation for this is that a material’s surface, instead of being uniform from the static perspective, is a mosaic of charge-donating and charge-receiving areas. To find out, they performed contact electrification using insulators (polycarbonate and other polymers), a semiconductor (silicon), and a conductor (aluminum). The charged surfaces were then scanned at very high resolution using Kelvin force microscopy, a variant of atomic force microscopy that is able to read the amount of charge in a surface.

Surface before static charging (top) and after (below). Science

The Kelvin force microscopy scans showed that the resulting surfaces were mosaics, with areas of positive and negative charges on the order of a micrometer or less across. All materials they tested, no matter what overall charge they had picked up, showed this mosaic pattern. The charges will dissipate over time, and the authors found that this process doesn’t seem to occur by transferring electrons between neighboring areas of different charge—instead of blurring into the surroundings, peaks and valleys of charge remain distinct, but slowly decrease in size. The authors estimate that each one of these areas contains about 500 elementary charges (that’s ±500 electrons), or about one charge for each 10nm2.

The reason that this produces a relatively weak charge isn’t because these peaks and valleys are small; the charge difference between them is on the order of 1,000 times larger than the average charge of the whole material. It’s just that the total area of sites with positive and negative charges are roughly equal (the two are typically within a fraction of a percent of each other). The distribution appears to be completely random, as the authors were able to produce similar patterns with a white noise generator that fluctuated on two length scales: 450nm and 44nm.

So, what causes these charges to build up? It’s not, apparently, the transfer of electrons between the surfaces. Detailed spectroscopy of one of the polymers (PDMS) suggests that chemical reactions may be involved, as many oxidized derivatives of the polymer were detected. In addition, there is evidence that some material is transferred from one surface to another. Using separate pieces of fluorine- and silicon-containing polymers allowed the authors to show that signals consistent with the presence of fluorine were detected in the silicon sample after contact.

The exact relationship between the charge transfer and the processes seen here—chemical reactions and the transfer of materials between the surfaces—isn’t clear at this point. But there are plausible mechanisms by which these processes could build up charges, and the authors very clearly intend to follow up on these findings.

In the meantime, you can be duly impressed with how much charge you can shuffle around when you build up static. Each square inch is equivalent to about 6.5 x 1014 square nanometers, so based on the authors’ numbers, that’s a lot of electrons.

Source: Ars Technica

Citation: Science, 2011. DOI: 10.1126/science.1201512

http://www.wired.com/2011/06/how-static ... ity-works/
On the Windhexe: ''An engineer could not have invented this,'' Winsness says. ''As an engineer, you don't try anything that's theoretically impossible.''
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Re: Sticky Tape Mystery

Post by Cr6 on Sun Jan 15, 2017 9:46 pm

Enjoy the many 'unexpected', 'mysterious' and 'unexplained' stuff they discover.

http://www.nature.com/news/2008/081022/full/news.2008.1185.html

Really interesting article Ciaolo.
Thanks LTAM for pulling up that old thread from TB since it clearly fits.  Really, when looking at this, I have to ask myself "What is 'Ionization'?" when looking at it. Structural changes that allow new surface charge flows?
 I think the nano-field is really troubled in general when they go this small... they can't really "predict" what happens at the nano-micron size when surfaces are quickly "changed" and that causes sudden charge-flow redirects?

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Re: Sticky Tape Mystery

Post by LongtimeAirman on Tue Jan 17, 2017 1:03 am

.
What is 'Ionization'?

From Wikipedia, https://en.wikipedia.org/wiki/Ionization
Ionization is the process by which an atom or a molecule acquires a negative or positive charge by gaining or losing electrons to form ions.

I would say ionization is second only to the electron as the most fundamental fact in understanding mainstream’s current definition of charge. So simple, everything is built upon it. Yet rub two balloons together and the nano-folk see high energy fractal charge distributions and declare mainstream broken.

Miles has made just a few changes: 1) charge is real repulsion caused by photon bombardment; 2) matter and anti-matter are just opposite photon spins which coexist naturally in all things; 3) All matter constantly recycles charge.

With that understanding static electricity becomes easy to describe. Atoms and molecules, with their attendant electrons, are in an equilibrium involving charge movement between the air and the “insulator” (glass, fur, quartz, amber, … ). Disturbing that equilibrium with mechanical motion, such as rubbing, exposes protons and reveals their strong underlying two-way atomic charge currents. It requires time for the material to adjust itself to the “surface changes”, depending on the availability of free electrons and positrons, drifting in the charge currents, to eventually plug up the proton inrush currents.  

Static electricity goes from being impossible to predict, to the simplest description of a disturbed charge equilibrium. I've been repeating this recently because it is easy for me to understand.

Do you know any nano-folk we can tell?
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Re: Sticky Tape Mystery

Post by Cr6 on Sat Jan 21, 2017 2:31 am

I don't know anyone working with nano personally... however, I saw this interesting link on Nano "construction" from Ted Talks. They compare it to building a 'statue' from "dust".

https://www.ted.com/talks/george_tulevski_the_next_step_in_nanotechnology

Also, this brings the whole idea of "plasmons" to the fore. Can Mathis' Charge Field explain this according to Occam's Razor?:

https://nbphotonics.uark.edu/presentations/
https://nbphotonics.uark.edu/publications/journal-articles/

Visualizing surface plasmons with photons, photoelectrons, and electrons

Both photons and electrons may be used to excite surface plasmon polaritons, the collective charge density fluctuations at the surface of metal nanostructures. By virtue of their nanoscopic and dissipative nature, a detailed characterization of surface plasmon (SP) eigenmodes in real space-time ultimately requires joint nanometer spatial and femtosecond temporal resolution. The latter realization has driven significant developments in the past few years, aimed at interrogating both localized and propagating SP modes. In this mini-review, we briefly highlight different techniques employed by our own groups to visualize the enhanced electric fields associated with SPs. Specifically, we discuss recent hyperspectral optical microscopy, tip-enhanced Raman nano-spectroscopy, nonlinear photoemission electron microscopy, as well as correlated scanning transmission electron microscopy-electron energy loss spectroscopy measurements targeting prototypical plasmonic nanostructures and constructs. Through selected practical examples from our own laboratories, we examine the information content in multidimensional images recorded by taking advantage of each of the aforementioned techniques. In effect, we illustrate how SPs can be visualized at the ultimate limits of space and time

http://pubs.rsc.org/en/content/articlelanding/2016/an/c6an00308g

Abstract
The current induced by incident photons on an gold grating slab is investigated numerically and experimentally. A semiclassical electrodynamic model is developed under the weak nonlinearity approximation. Electrons in the conduction band are treated as an electron gas in the presence of a self-consistent electromagnetic field. The model is solved by the finite element method and compared with measurements. The calculated current density as a function of incident angle and wavelength is found to be in qualitative agreement with the experimental measurements. The results show that increasing surface plasmon spatial variation enhances photon induced current.

http://aip.scitation.org/doi/full/10.1063/1.3590200
http://pubs.rsc.org/en/content/articlelanding/2016/an/c6an00308g

All-optical generation of surface plasmons in graphene

Surface plasmons in graphene offer a compelling route to many useful photonic technologies1, 2, 3. As a plasmonic material, graphene offers several intriguing properties, such as excellent electro-optic tunability4, crystalline stability, large optical nonlinearities5 and extremely high electromagnetic field concentration6. As such, recent demonstrations of surface plasmon excitation in graphene using near-field scattering of infrared light7, 8 have received intense interest. Here we present an all-optical plasmon coupling scheme which takes advantage of the intrinsic nonlinear optical response of graphene. Free-space, visible light pulses are used to generate surface plasmons in a planar graphene sheet using difference frequency wave mixing to match both the wavevector and energy of the surface wave. By carefully controlling the phase matching conditions, we show that one can excite surface plasmons with a defined wavevector and direction across a large frequency range, with an estimated photon efficiency in our experiments approaching 10−5.



http://www.nature.com/nphys/journal/v12/n2/abs/nphys3545.html

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Re: Sticky Tape Mystery

Post by LongtimeAirman on Mon Jan 23, 2017 12:29 am

http://physicsworld.com/cws/article/news/2014/oct/30/plasmons-convert-light-into-a-voltage

“When the laser was on resonance with the surface plasmon, no voltage was induced. Irradiation either side of the resonant frequency, however, did produce a voltage. When the wavelength was below 550 nm a negative potential was measured on the gold nanorods, while longer-wavelength light created a positive potential. The team found that the magnitude of the potential related to the rate at which the light absorbance changed with respect to the frequency of the light. The largest potential (which was negative) was produced by illumination at 500 nm. Atwater offers a thermodynamic explanation for this observation: "If you shine light on the structure, free-energy minimization will cause the structure to try to adjust its charge density to bring itself into resonance with the exciting light." The researchers have dubbed this phenomenon the plasmoelectric effect.

Both photons and electrons may be used to excite surface plasmon polaritons, the collective charge density fluctuations at the surface of metal nanostructures. By virtue of their nanoscopic and dissipative nature, a detailed characterization of surface plasmon (SP) eigenmodes in real space-time ultimately requires joint nanometer spatial and femtosecond temporal resolution.”

Cr6, Are you asking, What is the charge field description of plasmons? Thanks for the vote of confidence, I have no idea. I’ve never studied them, but “surface plasmon (SP) eigenmodes” sounds like quantum wave theory to me. However, “photons and electrons may be used to excite surface plasmon polaritons" implies photons are real. Are photons real or not?

Starting at https://en.wikipedia.org/wiki/Plasmon I see plasmons are one of a class of quasiparticles including: Davydov soliton, Dropleton, Exciton, Hole, Magnon, Phonon, Plasmaron, Plasmon, Polariton, Polaron, Roton, Trion. See https://en.wikipedia.org/wiki/Category:Quasiparticles for a larger listing which may include magnetic monopoles.

I would therefore recommend reviewing Miles’ paper.
296b. Solid Light? NO.  http://milesmathis.com/solidlight.pdf While analyzing the recent paper from Princeton, I explain high-temperature superconduction mechanically, including showing the physical cause of the Meissner Effect. This destroys BCS and RVB theory, Cooper pairs, polaritons, dimer math, and the rest of the fudged pseudo-explanations of solid-state physics. 30pp.

The Solid Light paper contains the quote. “Also notice the phrase “the dynamics of polaritons.” There is no such thing. By definition, “dynamics” has to do with forces and their effects on motion. Again by definition, “motion” has to do with the movement of real bodies. Polaritons are not real bodies. Polaritons are quasi-particles. Quasi-particles are not particles, hence the name. They are hole fillers. Fudges. You only need quasi-particles when you cannot solve physical problems with real physics. “

Your post from Sep2015 http://milesmathis.the-talk.net/t130-plasmons-convert-light-into-a-voltage covers the same subject and includes some additional references:
http://milesmathis.com/rain2.html
http://milesmathis.com/rainbow.html
http://milesmathis.com/rain3.pdf

I’ve been enjoying the review so much I’m losing track of the question.
.

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Re: Sticky Tape Mystery

Post by LongtimeAirman on Mon Jan 23, 2017 5:37 pm

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Both photons and electrons may be used to excite surface plasmon polaritons, the collective charge density fluctuations at the surface of metal nanostructures.

Using devices capable of “nanometer spatial and femtosecond temporal resolution”, a surface medium - say gold foil and air - exhibits non-linear resonant voltages when excited by photons and electrons. The greatest potential is a negative voltage, followed by a lesser magnitude positive, along with many other possible diminishing voltages.

Ok, I’ll take a first shot at describing plasmons in terms of the charge field. Using photon or electron excitation to select alternative available charge channels.

We aren’t disturbing the material mechanically, as with static electricity, exposing protons and their charge channels but we are able to inject photons or electrons that resonate with specific existing channels. We do not observe wave behavior we see alternative charge path currents.

There are many active charge channels within the gold foil, its geometry, in equilibrium with the surrounding air, the air's composition, availability of free electrons and positrons, temperature, and perhaps most importantly, its alignment with respect to the Earth’s field. The excitation laser or electron beam, at specific angles and intensities can resonate with most any of the many individual charge channels present, enabling the researchers to measure the specific charge flow potentials of those charge channels. I’m not certain we are taking individual or aggregate parallel channels, nevertheless we can see the high voltage capacities associated with the foil’s many parallel/symmetrical atomic charge recycling channels. The excitation blows away any impeding electrons and feeds channels directly, establishing a new charge flow equilibrium which our probe can measure.

I suppose the main potential measured is associated with pole to pole matter flow aligned vertically, a negative maximum; followed by the pole-to-pole antimatter, the smaller positive maximum. There are channels associated with the carousals or hooks of the gold atom in particular that do not involve currents as high as the pole-to-pole, but they are observable when excited in appropriate directions or excitation wavelength changes.

Does that sound reasonable? Any glaring errors?

In rain2 Miles shows us that visible light only comes in two frequencies. The proportion of the two makes a great deal of difference to us – in determining what color we see, though not necessarily to the charge channels themselves; I guess the important thing to the proton channels is the size differential between the photons and how they match the channels’ capacities.
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Re: Sticky Tape Mystery

Post by Cr6 on Sun Jan 29, 2017 11:44 pm

LongtimeAirman wrote:Cr6, Are you asking, What is the charge field description of plasmons?


Looks like you've taken a good approach.

Yes...basically. When we get to the nano-near single-atom layer... it is all basically charge-field. How the charge field works with structures at the nano-level may prove surprising. If quantum theory can't predict it reliably... then what will? Wink

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