Superconductivity is the transmission of current with no resistive losses, and is one of the most active areas of condensed matter physics research.
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Why is high temperature superconductivity so hard to solve?
The phenomenon of high temperature superconductivity has been known for decades, particularly layered cuprate superconductors. We know the precise lattice structure of the materials. We know the band ...
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Shine a light into a superconductor
A type-I superconductor can expel almost all magnetic flux (below some critical value $H_c$) from its interior when superconducting. Light as we know is an electromagnetic wave. So what would happen ...
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How can Ohm's law be correct if superconductors have 0 resistivity
Ohm's law states that the relationship between current ( I ) voltage ( V ) and resistance ( R ) is
$$I = \frac{V}{R}$$
However superconductors cause the resistance of a material to go to zero, and ...
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Usage of helium in MRIs
More and more articles pop up on the shortage of helium, and on the importance of it. Its usage in MRI's spring to mind for example. I looked it up and found out that helium is used for its 'low ...
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Can a superconducting wire conduct unlimited current?
A superconducting wire has no electrical resistance and as such it does not heat up when current passes through it. Non-superconducting wires can be damaged by too much current, because they get too ...
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871 views
Has Chandra Varma explained cuprate superconductivity?
Chandra Varma is a theoretical physicist at University of California, Riverside. A couple years ago, he gave a talk at my institution purporting to explain superconductivity in the cuprates. It all ...
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What is the “BCS Cooper pair condensation” as a physical phenomenon in terms of experiments?
"Thought" experiments and "numerical" experiments are allowed.
This question is motivated by the question Has BCS Cooper pair condensate been observed in experiment? ,
and by our recent research on ...
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What does the term liquid mean in condensed matter physics?
In condensed matter physics, people always say quantum liquid or spin liquid. What does liquid mean?
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Can superconducting magnets fly (or repel the earth's core)?
If a superconducting magnet and appropriate power supply had just enough $I\cdot s$ (current $\cdot$ length) so that when it was perpendicular to the earth's magnetic field, the force of the ...
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Is a superconductor really a super conductor?
It is known that a superconductor is a material with electrical resistance zero. My question is, it is exactly zero, a theoretical zero, or for practical realistic reasons it is effectively zero?
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How far away are we from resolving high temperature superconductivity?
What are the major recent findings and their corresponding contributions to an overall picture?
How well explained are the various regions of the dome, is there any thing that is pretty well ...
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477 views
How is stable levitation possible?
This question is with reference to the video in this blog post: http://www.universetoday.com/90183/quantum-levitation-and-the-superconductor/
My question is the following: how is the disc stable in ...
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A better conceptual model for cooper pairs in a superconductor
The conceptual model I have been introduced to for cooper pairs in a bulk superconductor is what I would call the "wake" model, where one electron deforms the positively charged lattice, changing the ...
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BCS wave function in Neutron stars
I've heard mentioned in various classes that neutron stars, like superconductors, are described by BCS theory. I know that in superconductors a key element in forming cooper pairs is a net attractive ...
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Superconducting Wavefunction Phase (Feynman Lectures)
In Volume 3, Section 21-5 of the Feynman lectures (superconductivity), Feynman makes a step that I can't quite follow. To start, he writes the wavefunction of the ground state in the following form ...
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Measuring the spin of a single electron
Is it possible to measure the spin of a single electron? What papers have been published on answering this question? Would the measurement require a super sensitive SQUID, Superconductive Quantum ...
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1answer
224 views
Relativistic drift velocity of electrons in a superconductor?
Is there a formula for the effective speed of electron currents inside superconductors?
The formula for normal conductors is:
$$ V = \frac{I}{nAq}$$
I wonder if there are any changes to this ...
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How do superconducting materials float in magnetic field?
The movie Avatar got me interested in the subject, but so far I only found sophisticated articles loaded with unfamiliar words. Is there a simple way to explain how magnetic field affects ...
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1answer
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A question on the doped Kitaev-Heisenberg model?
Recently, some groups have studied the effects of doping the Kitaev model on honeycomb lattice(e.g.,http://arxiv.org/abs/1109.6681 and http://arxiv.org/abs/1109.4155) and their calculations show the ...
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Superconductivity reasons (Intutitive)
Superconductivity
I read in a book "Physics - Resnik and Halliday" the explanation of Type-I Superconductors{cold ones} that:
The Electrons that make up current at super-cool temperatures move in ...
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Meissner Effect for Type-II Superconductors
I was wondering whether the breakdown field strength for the Meissner effect may be attributed to the Zeeman effect? I can see the latter (along with the Stark effect) to be more analogous to electron ...
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Intuitive explanation to why superconductivity breaks at high temperatures
I was recently caught up in a situation where I tried to explain to someone with only vary basic knowledge of physics (notion of atoms and electrons, etc.) what causes superconductivity. One thing I ...
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270 views
Maximum electron-phonon coupling SC temperature
In many articles and web pages I found people claiming that the maximum critical temperature for superconductivity in the BCS framework is about 40K.
Sometime, more accurate writers report that the ...
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1answer
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What do we know of superconductivity in thin layers?
motivated by another question, i wonder if there are special properties of superconductivity when restricted on 2D or very thin layers related to the effective permittivity in function of the ...
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London penetration depth
Which type two s-wave superconductor has the smallest London penetration depth? What is l_lamda ?
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Why can't a superconductor make a DC motor self sustaining?
Superconducting wire can host a low current magnetic field. I do not know if it supports a corresponding electrical field.
Can a superconducting wire that sustains a current accelerate a DC motor? ...
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What does “particle number conservation” mean in condensed matter physics?
What exactly does it imply about a condensed matter system to have particle number conserved or not conserved?
For example, why does the superconducting phase break particle number conservation while ...
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Why is the AdS/CFT approach to superconductors rarely cited in condensed matter publications?
Let me put things into perspective by comparing with other applications of string theory. Nowadays review papers written by cosmologists about inflation models often discuss string theory scenarios ...
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How come a photon acts like it has mass in a superconducting field?
I've heard the Higgs mechanism explained as analogous to the reason that a photon acts like it has mass in a superconducting field. However, that's not too helpful if I don't understand the latter. ...
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Pairing symmetry / superconducting gap symmetry
I'm not (yet :-) ) an expert on superconductors, but one term I keep hearing all the time is that of the symmetry of the gap, which can be s-wave, p-wave, d-wave etc.
What exactly is the symmetry ...
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What do massive photons have to do with superconductivity?
I keep reading that the idea of massive photons leads to an explanation of the Meissner effect but I fail to see how photons are involved with the repulsion of fields inside a superconductor.
How ...
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Aharonov-Bohm Effect and Flux Quantization in superconductors
Why is the magnetic flux not quantized in a standard Aharonov-Bohm (infinite) solenoid setup, whereas in a superconductor setting, flux is quantized?
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What are the easiest to get/make LN2 superconductors?
I am starting to build multistage Peltier cooler at the moment, and it should be able to reach -100C at least (but if I fail I can always get boring LN2).
Doing some experiments with superconductors ...
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BCS theory, Richardson model and Superconductivity
I'm studying Richardson Model in second quantization. There are many initial points that I don't understand:
We supposed that an attractive force between 2 electrons exists, due to electron-phonon ...
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Layman explanation for superconductivity?
I'm interested in reading an explanation of superconductivity, but though I have an undergraduate degree in engineering, I'm not sure I'm up to reading a detailed mathematical treatment of the theory. ...
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Can i use coils with compressed air to make a superconductor?
What im saying is inside pipes i am going to use compressing so that that in the places with low pressure they cool the superconducotor. is this possible? Can i use this concept to make ...
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Superconductors and electrical fields
I have been looking around to figure out how superconductors are made. What ways are there to create a superconductor that don't involve a coolant like liquid nitrogen? Is it possible to cause a ...
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Induction cooker + superconductive pot
What will happen if I put a super-conductive object on an induction cooker, and turn the cooker on?
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How does phonon cause two electrons to attract each other?
We know that like charges repel each other. But my professor claimed that two electrons can attract each other as well. What he said was that due to screening an electron traveling at some speed wont ...
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Why does a superconductor obey particle-hole symmetry?
We normally solve the Bogoliubov-de Gennes (BdG) equations in order to compute the energy spectrum of a superconductor. The Nambu spinor is a common object that is used in formulating these equations. ...
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Zero Resistance in Quantum Hall Effect and Superconductivity
What is the difference between the zero resistance of $R_{xx}$ in integer quantum Hall effect and the zero resistance in superconductivity?
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superconductor levitating in earth's magnetic field? [duplicate]
Possible Duplicate:
Can superconducting magnets fly (or repel the earth's core)?
I've seen superconductors levitating on magnets. But is it possible for superconductors to levitate on ...
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Superconducting gap, temperature dependence: how to calculate this integral?
Tinkham (page 63) states that the temperature dependence of the gap energy of a superconductor $\Delta(T)$ can be calculated using the following integral:
How can this actually be carried out? I am ...
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Quantum levitation (locking) 3mm thick disk could carry 1000kg small car claim
I watched this TED presentation: http://www.ted.com/talks/boaz_almog_levitates_a_superconductor.html
It is about superconductivity and quantum levitation. It tells that super-thin, three-inch disk ...
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Electrical energy storage in superconductors
I am a first year A-level student and I am doing a project about the possibility of storing electrical energy in a superconductor. I have researched and I am aware of the critical current density and ...
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Flow of supercurrent in a superconductor
I have two questions one practical and one theoretical. Even though I have a decent understanding of superconductivity both phenomenological as well as theoretical (i.e. BCS), some things just slipped ...
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1answer
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Effects of parallel superconducting plates
Assuming the existence of virtual particle field ( zero point energy field) Casimir force is produced by 2 parallel conducting plates excluding some of the frequencies between the plates, if these 2 ...
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Alternative to Cooper pairing in superconductivity
BCS theory, in which electrons form Cooper pairs, has been successful in explaining conventional superconductivity. Physicists have adopted similar pairing mechanism in an attempt to explain ...
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What is meant by the quantum integrity in a superconducting loop
I encountered this in the context of using squid microscopy to test for d-wave pairing in an iron arsenide superconductor where the goal of the experiment was to detect half integer flux quantum ...
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can Superconductivity be used to repel water?
Can water be repeled with the force from superconductivity gathering current on the surface cuased by Faraday law of induction? I'm trying to make a ROV that can run underwater that uses ...
