Tagged Questions
3
votes
1answer
98 views
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 ...
0
votes
0answers
55 views
Some questions about the edge states for time-reversal invariant topological superconductors?
Stimulated by my some recent calculations on edge states(ES) for time-reversal invariant(TRI) topological superconductors(TS) as well as many questions concerning the "edge states" in Physics ...
1
vote
1answer
90 views
What is the importance of the Fermi energy $E_F$ or the chem. potential $\mu$ for topological superconductors
A lot of effort is put into shifting the Fermi energy of a topological insulator to exactly zero which then provides some advantages when this TI is coupled with a superconductor.
I don't understand ...
3
votes
1answer
78 views
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 ...
5
votes
1answer
180 views
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 ...
3
votes
2answers
225 views
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. ...
9
votes
1answer
212 views
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 ...
3
votes
1answer
98 views
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 ...
3
votes
1answer
182 views
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?
5
votes
2answers
172 views
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 ...
5
votes
1answer
245 views
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 ...
1
vote
1answer
84 views
What papers detail the early research on heavy fermion superconductors?
Can someone point me to the papers detailing when/where/how heavy fermion superconductors were first synthesized, tested and documented?
2
votes
2answers
174 views
Has BCS Cooper pair condensate been observed in experiment?
Feshbach resonance in s-wave scattering states a BCS Cooper pair condensation at B-field just above the resonance where the scattering length a <0. Just wondering if the condensation has been ...
8
votes
3answers
278 views
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?
2
votes
1answer
115 views
Crystal magnetic response only skin deep?
The Hamiltonian for a single electron in a magnetic field reads
$$H=\left(\frac{{\bf p}^{2}}{2m_{e}}+q_{e}\phi\right)+\mu_{B}\left({\bf \hat{L}}+g{\bf \hat{S}}\right)\cdot{\bf ...
5
votes
4answers
199 views
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 ...
1
vote
2answers
104 views
Reference needed for Iron-based superconductors
Iron-based superconductor is a class of high-$T_c$ superconductors discovered in 2008.
Are there any review papers about these superconductors yet? If not, which are the key papers in the field?
9
votes
1answer
869 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 ...
7
votes
1answer
200 views
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 ...
7
votes
1answer
388 views
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 ...
7
votes
2answers
434 views
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 ...
12
votes
3answers
573 views
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 ...
