Questions tagged [superconductivity]
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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What "transformations" did Abrikosov use in 1958 to get the famous $11-2\log{2}$ result in fermi-liquid theory?
How does one obtain the final integral expression in the appendix of Abrikosov and Khalatnikov's 1958 paper: $\ \ \ $ "Concerning a model for a non-ideal fermi gas" $\ \ \ $ ???
Below, in Bold, I ...
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Is the uniqueness theorem correct in superconductivity?
There is an uniqueness theorem in electromagnetism. It says that the solution of Maxwell's Equations is determined uniquely by boundary conditions.
We can treat superconductivity as a completely ...
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What is the physical meaning of phase in a superconductor?
I am trying to understand the physical meaning of phase in the order parameter of a superconductor. In particular,I was looking at this article that states the phase $e^{i\theta}$ in the BCS ground ...
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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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Why haven't we found thermal superconductors?
First of all I want to apologize if this is a stupid question. I'm a layman who's merely very interested in physics, without a degree to my name.
I was trying to research electric superconductors ...
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What is the RC time constant in a superconductor?
In conventional conductors, the RC time constant is the time required to charge or discharge a capacitor through a resistor by ≈ 63.2 percent of the difference between the initial value and final ...
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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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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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Goldstone modes and Anderson-Higgs mechanism in the context of BCS theory
I'm already familiar with the "Mexican hat" story of Anderson-Higgs mechanism in Landau-Ginzberg theory. However, I have never seen anyone talking about Goldstone and Higgs mechanism in the context of ...
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Difference between $\nu=5/2$ quantum Hall state, chiral p-wave superconductor, He 3
I am interested in the relation between the following three phases of matter (in 2D):
chiral $p$-wave superconductor (spineless $p_x + i p_y$ pairing)
$\nu=5/2$ fractional quantum Hall state
A-phase ...
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Unstability of Fermi surface in superconductors & Cooper problem
The Fermi Energy is defined as the highest energy occupied at $T=0$ by a system composed of Fermions.
When we study the Cooper problem as an introduction to BCS theory, we say: let's put a pair of ...
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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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Is there a database or a classification of High-temperature superconductors?
I was wondering if there exists a list with all (or most of) the High-$T_c$ superconductor materials.
In particular I'd like to know if there are databases or review that classifies them by their ...
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Question about superconductivity
A long cylinder of radius $R$ is made from two different material. Its radius $r<r_0$
$(r_0<R)$ part is a material with superconducting transition temperature $T_1$, and its $r_0<r<R$ ...
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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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How to compute the density of state from the Green function?
I'd like to plot the density of state (DOS) for a specific system, say an s-wave BCS superconductor, the Green function of which is
$$G\left(p,\omega\right)=\dfrac{\omega+\xi}{\omega^{2}-\xi^{2}-\...
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Why do superconductors have a maximum current density?
If superconductors have no resistance, what prevents you making the cross-section as small as you can handle, if there will be no power dissipated anyhow?
Is there a limit on the magnetic field that ...
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Charge balance and Bogoliubov quasiparticles
Before trying to understand charge imbalance in superconductors (eg Hübler et al., Phys. Rev. B 81, 184524, Quay et al., Nature Physics 9,84–88 (2013)) I thought I had better check I understand the ...
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What is a d + id superconductor and why does it break time reversal symmetry?
There are a lot of publications dealing with d-wave and d + id superconductivity, but I found no satisfying answer what exactly makes a superconductor d + id and why they break time reversal symmetry. ...
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Why aren't superconductors shiny? [duplicate]
Superconductors are really good at conducting electricity. Should they not reflect light very well too?
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Superconductive magnet as a source of energy?
Could we charge a superconductive magnet and use it as a source of energy?
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What is superconducting coherence length?
I'm an electronics student, and don't know much about some physics concepts.
I was studying superconductivity and came to the London equation, Meissner effect and BCS theory.
I kind of understood ...
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Can current be induced in a superconductor?
Moving a magnet close to a conductor induces a current. If it consists of a superconducting material with resistance $R=0$, then my textbook says:
Then the induced current will continue to flow ...
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How does current flow in superconductors if Cooper pairs have zero momentum?
I've been reading a lot of condensed matter textbooks, which state both that the net momentum of a Cooper pair in a superconductor is zero, and that Cooper pairs have momentum when they carry current.
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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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How does quantum trapping with diamagnets work?
I just saw this demonstration by someone from a Tel Aviv University lab.
What they achieved there is mind blowing. I myself own a levitron that uses the Hall effect to levitate a magnet, the problem ...
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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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Topological number of 1-D p-wave superconductor---Kitaev model/wire
After learning the Kitaev model, I tried to reformulate it and encounter some conceptual loopholes of my own.
Here the setting:
Given the 1-D chain Hamiltonian (differed from original form proposed ...
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Superconductivity and time-reversal symmetry
Let us consider a system of a 1D edge of a 2D topological insulator in proximity to an s-wave superconductor. The system is described by the Hamiltonian:
$$
H =\frac{1}{2}
\int \mathrm{d}x \
\Psi^{\...
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How is a Majorana fermion created when a s-wave superconductors is in proximity to a topological insulator (e.g. via an antidot)
Kane and Fu proposed a few geometries how to create Majorana zero modes using a s-wave superconductor in proximity to a 3D topological insulator (TI).
-> http://www.physics.upenn.edu/~kane/pubs/p56....
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