1
vote
0answers
38 views

How Does The Macroscopic Wavefunction Build Up?

How does the macroscopic wavefunction (the order parameter) builds up from zero value to the a finite value when liquid He undergoes a transition from normal to the superfluid state? How does it ...
0
votes
0answers
13 views

relating the AB transition temperature in a superfluid with different coherence lengths

i have two sets of data. one leads to a value for the transition temperature from the A phase superlfuid to B phase. This was performed in a thin slab, which was too thin to observe the A-B ...
4
votes
0answers
66 views

Third-order topological quantum phase transition in p+ip superfluid

A two-dimensional spinless non-relativistic p+ip superfluid undergoes a quantum phase transition between the BCS (weakly-coupled) and BEC (strongly-coupled) regimes. This transition is driven by ...
1
vote
2answers
50 views

Bulk modulus of Liquid helium and first sound

Does anyone know where to find the bulk modulus of liquid helium ? I've been looking all over the internet but everywhere I get N/A. Any tips ? I'd need it to estimate the speed of first sound in ...
3
votes
1answer
163 views

Symmetry breaking in Bose-Hubbard model

According to Landau's symmetry breaking theory, there is a symmetry breaking when phase transition occurs. What is the symmetry breaking of superfluid-Mott insulator transition in Bose-Hubbard ...
2
votes
1answer
155 views

periodic boundary conditions for vortex in a square lattice

I am trying to follow this paper and track the dynamics of vortex motion on a discrete (square) lattice. The idea is to simulate the time evolution of the Gross-Pitaevskii (GP) equation, which reads ...
10
votes
2answers
307 views

How to understand the emergent special relativity in the superfluid?

The superfluid vacuum theory was proposed to understand some features of the vacuum (aether) from the emergence point of view. Although made up of non-relativistic atoms, the low-energy excitations of ...
15
votes
2answers
550 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 ...
7
votes
1answer
130 views

Why is the BCS trial function valid across the BEC-BCS crossover?

In one of the two main theoretical approaches used in describing ultracold Fermi gases and the BEC-BCS crossover, the so-called BCS-Leggett approach, the starting point is the BCS trial wavefunction: ...
3
votes
0answers
75 views

Two-fluid description of superfluidity

I'm trying to teach myself about superfluidity and I'm slightly confused on the ''two-fluid'' description. From what I understand, the superfluid is considered to be a mixture of two fluids, a ...
3
votes
3answers
591 views

Looking for a complete review of the BEC-BCS crossover

I'm looking for comprehensive review of the BEC-BCS crossover, both from a theoretical point of view, and from a experimental one. Even something at textbook level, but exhaustive, would be OK, but I ...
10
votes
3answers
369 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?
4
votes
1answer
351 views

Helium-4 superfluidity and gauge symmetry breaking

Is there an accessible account of superfluidity in Helium-4 as a manifestation of "global gauge symmetry" breaking? And what is meant by "global gauge symmetry"? I was taught that gauge symmetries ...