Electrons and liquid helium advance understanding of zero-resistance

February 2, 2016 by Olga Garnova
A cell (container) where the electrons on liquid helium experiments are conducted. Credit: OIST

The end of Moore's Law, the prediction that transistor density would double every two years, was one of the hottest topics in electronics-related discussions in 2015. Silicon-based technologies have nearly reached the physical limits of the number and size of transistors that can be crammed into one chip, but alternative technologies are still far from mass implementation. The amount of heat generated during operation and the sizes of atoms and molecules in materials used in transistor manufacturing are some of problems that need to be solved for Moore's Law to persist.

Atomic and molecular sizes cannot be changed, but the heat problem is not unsolvable. Recent research has shown that in two-dimensional systems, including semiconductors, electrical resistance decreases and can reach almost zero when they are subjected to magnetic and microwave influence. Electrical resistance produces a loss of energy in the form of heat; therefore, a decrease in resistance reduces heat generation. There are several different models and explanations for the zero-resistance phenomenon in these systems. however, the scientific community has not reached an agreement on this matter because semiconductors used in electronics are complex and processes in them are difficult to model mathematically.

Research conducted by the Quantum Dynamics Unit at Okinawa Institute of Science and Technology graduate University (OIST) could represent an important step in understanding two-dimensional semiconductors. The Unit's latest paper, published in Physical Review Letters, describes anomalies in the behaviour of in electrons on liquid helium two-dimensional system.

Copper mirrors direct and focus microwave photons in electrons on liquid helium system. The focusing mirror (on the left) is made by pressing a hard stainless steel ball (also shown in the picture) into a soft piece of copper. The flat mirror (on the right) shows two concentric circular electrodes (aka a Corbino pair) that are used to measure electron conductivity. Credit: OIST

The system is maintained at a temperature close to absolute zero (-272.75ºC or 0.4K) to keep the helium liquefied. Extraneous electrons are bound to the helium surface because their presence causes slight changes in the orbits of helium electrons, inducing a subtle positive charge at the helium surface. At the same time, lack the energy required to penetrate the surface to enter the liquid. The resulting system is ideal for studying various electron properties, as it has virtually zero impurities, which avoids artefacts caused by defects of surface and structure, or due to the presence of other chemical elements. Prof. Denis Konstantinov, head of the Quantum Dynamics Unit, and his team study conditions under which electrons can violate selection rules regulating transitions from one state to another.

In a macro-world we perceive transitions from one state to another as happening gradually. For example, a person travelling from town A to town B can make an infinite number of stops. In micro-world that is not always the case. Properties, such as energy, position, speed, and colour, can be quantised, i.e. they can occur only in discrete quantities. In other words, the traveller can be either in town A, or town B, but not somewhere in-between.

Since electron energy is quantised, electrons can occupy only specific energy levels. Quantum theory predicts that in a two-dimensional electron system, where moving electrons are confined to one plane, under a strong magnetic field electrons also will be restricted to climbing only one step of the energy level ladder at a time. however, the experiments show that electrons can jump to higher energy levels, skipping levels between. Prof. Konstantinov and his team are very excited about this discovery: "It is not everyday that we get a chance to observe the violation of quantum theory predictions!"

In order to study abnormalities in electron state changes, the scientists applied a strong vertical magnetic field and then bombarded the electrons on liquid helium system with microwave photons. Credit: OIST

In order to study abnormalities in electron state changes, the scientists applied a strong vertical magnetic field and then bombarded the system with microwave photons. Under these conditions, selection rules seem to stop working. Prof. Konstantinov says that his group had theorised that such a phenomenon is possible and now they have proven it.

Selection rules describe a theoretical, absolutely pure, and homogenous system with no disorders. Real-life systems are more complex. In the case of electrons on helium, the system is pure and homogenous, but the surface of is nonetheless disturbed by capillary waves—ripples associated with the surface tension and similar to small, circular ripples in a pond when a pebble is tossed into the water. The height of these ripples is only the diameter of a hydrogen atom, but in combination with microwave radiation they create enough deviation from an ideal system for selection rules to change.

Conditions modelled in the Quantum Dynamics Unit's experiment are similar to those that led to observations of zero resistance in semiconductors. however, the electrons on helium system is relatively simple and can be described mathematically with great precision. Studying this system will further the development of quantum physics and will contribute to our understanding of electrons and various electrical phenomena. moreover, with some adjustments models, based on electrons on helium systems can be adapted to more complex systems, such as two-dimensional semiconductors.

Explore further: Incompressible electrons

More information: R. Yamashiro et al. Photoconductivity Response at Cyclotron-Resonance Harmonics in a Nondegenerate Two-Dimensional Electron Gas on Liquid Helium, Physical Review Letters (2015). DOI: 10.1103/PhysRevLett.115.256802

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Eikka
2.3 / 5 (6) Feb 02, 2016
The end of Moore's Law, the prediction that transistor density would double every two years


That's not Moore's law.

Might seem like a petty point, but factual errors like that have profound impact on the public understanding of science and society. If you throw "facts" like that out there, people take them for granted, and think that the transistor density has indeed been doubling every two years when it hasn't.

No wonder people believe in all sorts of bullcrap like singularity and conspiracy theories, when the media continuously mis-represents the state of progress in technology.
ProcrastinationAccountNumber3659
3.3 / 5 (7) Feb 02, 2016
That is the basics of moore's law. I like how you say that is not and do not even state what you think is correct. You just rant instead.

http://spectrum.i...ores-law
Azrael
2.3 / 5 (3) Feb 02, 2016
The end of Moore's Law, the prediction that transistor density would double every two years


That's not Moore's law.

Might seem like a petty point, but factual errors like that have profound impact on the public understanding of science and society. If you throw "facts" like that out there, people take them for granted, and think that the transistor density has indeed been doubling every two years when it hasn't.

No wonder people believe in all sorts of bullcrap like singularity and conspiracy theories, when the media continuously mis-represents the state of progress in technology.


If singularities are impossibilities/mathematical artifacts/what have you, and you've any proof -at all- of what could exist at the bottom of the insane gravity well of a black hole, I'd love to hear it.
promile
Feb 02, 2016
This comment has been removed by a moderator.
bschott
4 / 5 (4) Feb 02, 2016
If singularities are impossibilities/mathematical artifacts/what have you, and you've any proof -at all- of what could exist at the bottom of the insane gravity well of a black hole, I'd love to hear it.


You just asked Eikka to prove what could exist inside a theoretical object.....good one.
bschott
4 / 5 (4) Feb 02, 2016
That is the basics of moore's law. I like how you say that is not and do not even state what you think is correct. You just rant instead.

http://spectrum.i...ores-law


A prediciton is not a law, just because they decide to call it one. If it was a law, it has been broken several times as we have not witnessed a continuous doubling every 2 years since 1965 as predicted.
Steelwolf
2.6 / 5 (5) Feb 02, 2016
Moore's 'Law' that there would be a doubling every two years has been broken before, but the advancements immediately after that two year window were more than a doubling anyhow, so it still worked out to a degree. Doubling of the transistors usable at any one time gives rise to higher (doubled) computing power, which is what Moore was concerned with.

Watching the paid anti-REAL-science troll Eikka self-destruct on that one was beautiful! Just because something is not 'mainstream science' does not mean that it is not a real effect or that it wont overthrow previous ideas. Remember, Einstein flunked out of math because HE saw that they we doing it wrong, but that was THE Mainstream WAY. Often the non-mainstream science theories are the correct ones, look at Galileo and Copernicus vs today's view of our Solar system.

Mainstream does not mean 'Absolutely Correct' yet they pay a LOT of money to trolls to keep the real science behind their own bars of money and power!
bschott
4.2 / 5 (5) Feb 02, 2016
Remember, Einstein flunked out of math because HE saw that they we doing it wrong, but that was THE Mainstream WAY. Often the non-mainstream science theories are the correct ones, look at Galileo and Copernicus vs today's view of our Solar system.


Very well said. Einstein never stopped "figuring things out"....the physics community just stopped paying attention when they thought they were on the right path.

Mainstream does not mean 'Absolutely Correct'


It certainly doesn't.

yet they pay a LOT of money to trolls to keep the real science behind their own bars of money and power!


Such is the MO of people trying desperately to hold on to their power and prestige, expected in the corporate world, not the science world.

antialias_physorg
4.5 / 5 (4) Feb 02, 2016
Remember, Einstein flunked out of math

No. Don't remember it - because it's an urban myth. It was one of these made up factoids on "Ripley's Believe it or Not" that just sounded too good not to print (in it they even claimed Einstein was a mathematician...which just goes to show how carefully they vetted that one)
Phys1
2 / 5 (4) Feb 02, 2016
@bs
You agree with the myth on Einstein because you like it.
Not because it is factual. Repent .
bschott
3.7 / 5 (3) Feb 02, 2016
Perhaps the urban myth was rooted in his first attempt to gain entrance to a university. (bottom of second paragraph)

http://www.shmoop...erk.html

Good thing he persevered through the setbacks caused by the attitudes of rigidity and superiority he encountered.

bschott
3 / 5 (4) Feb 02, 2016
@bs
You agree with the myth on Einstein because you like it.
Not because it is factual. Repent .


No dipshit, it wouldn't have surprised me in the least if Steelwolfes comment was accurate for the very reason he stated, that I didn't check it was my fault but as you can see....he didn't ace everything either. The contributions Einstein made to physics haven't been realized as of yet, since his later work is still ignored by morons who can;'t wrap their heads around how magnetism works....yes.....you.
Phys1
5 / 5 (3) Feb 02, 2016
That is the basics of moore's law. I like how you say that is not and do not even state what you think is correct. You just rant instead.

http://spectrum.i...ores-law


A prediciton is not a law, just because they decide to call it one. If it was a law, it has been broken several times as we have not witnessed a continuous doubling every 2 years since 1965 as predicted.

Here is a plot that says we actually did withess a doubling every two years:
https://en.wikipe...2011.svg
Phys1
3 / 5 (4) Feb 02, 2016
still ignored by morons who can;'t wrap their heads around how magnetism works....yes.....you.

So you are an unrecognised genius. And it is because of me. That's pathetic.
Why don't you explain once more that the solar system and the galaxy are held together by magnetism alone?
gculpex
5 / 5 (1) Feb 02, 2016
still ignored by morons who can;'t wrap their heads around how magnetism works....yes.....you.

So you are an unrecognised genius. And it is because of me. That's pathetic.
Why don't you explain once more that the solar system and the galaxy are held together by magnetism alone?


All I'm going to say is just because it is most likely doesn't mean it is the only one or way. Until we find out the final answers, everything is up for grabs.
bschott
1 / 5 (1) Feb 03, 2016
still ignored by morons who can;'t wrap their heads around how magnetism works....yes.....you.

So you are an unrecognised genius.


No, you are a recognizable idiot.

And it is because of me. That's pathetic.


Wow...dad? Why did you go?

Why don't you explain once more that the solar system and the galaxy are held together by magnetism alone?


Not the solar system, although it plays a much bigger part than it's given credit for. But star positions relative to each other in the galaxy, again, yes. That has only got to be the 5th time but I get that you're slow.

Phys1
3 / 5 (2) Feb 03, 2016
@bs
But a back of the envelope calculation says that is utter* nonsense.
What have you got to say to that Mr Unrecognised Genius (sorry ...) ?

*, utter etc.
Phys1
5 / 5 (1) Feb 03, 2016
still ignored by morons who can;'t wrap their heads around how magnetism works....yes.....you.

So you are an unrecognised genius. And it is because of me. That's pathetic.
Why don't you explain once more that the solar system and the galaxy are held together by magnetism alone?


All I'm going to say is just because it is most likely doesn't mean it is the only one or way. Until we find out the final answers, everything is up for grabs.

The only, deceptively simple, requirement is that you make sense.
A theory should be in agreement with observations, or overthrow them, and it should be consistent, so mathematical.
bschott
1 / 5 (1) Feb 03, 2016
All I'm going to say is just because it is most likely doesn't mean it is the only one or way. Until we find out the final answers, everything is up for grabs.


My main statement has always been that "it is the prime driver of structure on the universal scale". You are 100% correct that it isn't the only one. Equations based around gravity treat it as though it is the only one which why they are so far off without the 5 X more matter. Gravity is a factor, but until we actually figure out its true nature( for starters that it is a force without a particle that mediates it) everything is, as you stated up for grabs.
bschott
1 / 5 (1) Feb 03, 2016
But a back of the envelope calculation says that is utter* nonsense


Calculation of what?

The only, deceptively simple, requirement is that you make sense.


Given the statements you have made here, you are in no position to judge whether I make sense. You have typed some really stupid things based on your belief in the standard model.

A theory should be in agreement with observations


The theory you support increased the universal mass content by a multiple of five without it actually being there in order to explain our observations...wake up.

or overthrow them


A theory cannot overthrow observations...unless you believe mainstream theorists.

and it should be consistent, so mathematical.


Not when it's fantasy math as per my mass comment above. It is not consistent to add a variable as large as DM without verifying it's existence as modeled.

Attractive AND repulsive force is the only way to to hold relative position.

bschott
1 / 5 (1) Feb 03, 2016

Here is a plot that says we actually did withess a doubling every two years:


3 dots cover a 10 year span between 1985 and 1995. Those were the 386, 486 and pentium....so i guess your WIKI chart was done by microsoft being as Apple processors are absent? The plot shows leaps and bounds that work out to an average of doubling every 2 years. Not actual cyclic 2 year increases. Learn to read AND look at the chart. Maybe a course in critical analyses might help you spot the massive incongruencies you habitually miss when touting your beliefs to the world...or, if it is wilful ignorance which is far more likely....we can keep chatting.

One more thing, you shouldn't engage people you brag about putting on ignore and advise others to also. If you had any credibility this would have damaged it and since you appear to think you have credibility...well, do the math. :P
Phys1
3 / 5 (2) Feb 03, 2016

Here is a plot that says we actually did withess a doubling every two years:


3 dots cover a 10 year span between 1985 and 1995. Those were the 386, 486 and pentium....so i guess your WIKI chart was done by microsoft being as Apple processors are absent? The plot shows leaps and bounds that work out to an average of doubling every 2 years. Not actual cyclic 2 year increases. Learn to read AND look at the chart. Maybe a course in critical analyses might help you spot the massive incongruencies you habitually miss

Not only do you know better that all physicists, now you know better than the entire semiconductor industry.
You know better than the CEOs of Samsung, TSMC, Intel, Global Foundries combined.
I strongly advise anyone here to put you on ignore or crush you as the scientific and technological insect that you are.
bschott
1 / 5 (1) Feb 03, 2016

Not only do you know better that all physicists, now you know better than the entire semiconductor industry.


Well, i examined the chart and stated exactly what I saw, anyone with eyes that are connected to their brain will see the exact same thing. If this application of physical senses somehow puts me a leg up on all physicists and the semi-conductor industry...yup.

You know better than the CEOs of Samsung, TSMC, Intel, Global Foundries combined.


Are their eyes connected to their brains?

I strongly advise anyone here to put you on ignore or crush you as the scientific and technological insect that you are.


I strongly advise you to change tampon brands, move out of moms house and find yourself a sexual companion that isn't already part of your physiology.

Put me back on ignore or expect this everytime we chat miss, you are not worth any attempt made to tolerate you.
Phys1
3 / 5 (2) Feb 03, 2016
just when you think the crank cannot sink any lower.
"are there eyes connected to their brains"
"tampon brands"
you are now also disgusting.
bschott
1 / 5 (1) Feb 03, 2016
just when you think the crank cannot sink any lower.
"are there eyes connected to their brains"
"tampon brands"
you are now also disgusting.


If you making thoughtless remarks and me pointing them out is sinking lower, call me the titanic.

If you are disgusted by the thought of tampons, sorry...try pads then.
Phys1
3 / 5 (2) Feb 03, 2016
A paria.
Steelwolf
not rated yet Feb 04, 2016
I think that part of the problem with the whole Gravity/DM VS Plasma/EU is that the early scientists were measuring the net forces of attraction and Calling it all 'Gravity'. Obviously since we now know a LOT more on the atomic and quantum scales, and can see that gravity is a weak force while electromagnetism is a stronger force BUT THEY BOTH ADD to form the effects that we call 'Gravity'. We keep looking for a single mechanism for gravity when it almost assuredly has to do with a combination of effects, likely not only particle attraction via gravity and charge, but also the magnetic fields in space, the Van Allen Belts, actually create a tiny downward force due to the magnetics and since most matter has a charge due to electron shell valence or elementary particle charge, it can be held in that magnetic field and Has to react to it.

Gravity as the net sum of several properties is something that needs to be resolved before meaningful answers will be forthcoming.
Steelwolf
not rated yet Feb 04, 2016
Ya Know Phys 1, Apple was going to come out with a wide-screen phone/tablet but the ladies in the Marketing Department stopped it when the scientists/engineers creating it tried to release it as a Max IPad...
Phys1
not rated yet Feb 05, 2016
@Steelwolf
THEY BOTH ADD to form the effects that we call 'Gravity'.

No they don't and "we" don't.
pepe2907
not rated yet Feb 06, 2016
Moore's law? Is this really the problem in an article, which throws the "truth" that energy, position, speed and /attention!/ color are quantifiable /and yes, energy generally speaking is not quantifiable either, quantifiable is only the amount of energy, necessary to move a specific particle from a specific state to a specific different one in a specific system, like an atom, for "position" and "speed" somebody really needs to retake it's physics classes, specifically the ones related to Relativity, and about "color" I don't want even to start/.
But just by the way there is a logic flaw too in that same paragraph - if a bus can take infinite stops covering a distance that means space is not discrete. :)
pepe2907
5 / 5 (1) Feb 06, 2016
@Steelwolf:

"Often the non-mainstream science theories are the correct ones..."

Any idea of how many non-mainstream theories are being debunked for every "mainstream one"? :)

And "...the Van Allen Belts, actually create a tiny downward force due to the magnetics and since most matter has a charge due to electron shell valence..." is a really elaborate nonsense...

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