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3
votes
1answer
60 views

Charge-Vortex Duality for Bosons

Consider a (2+1)d continuum field theory with the Minkowski action $$\mathcal{L}=|\partial\phi|^2-r|\phi|^2-u|\phi|^4,$$ where $\phi$ is a complex field. The theory undergoes a quantum phase ...
1
vote
1answer
116 views

Vortex in superfluid?

I'm studying superfluid helium 4. I have studied that the superfluid has a velocity : $ \vec{v}_s = \frac{\hbar}{m} \vec{\nabla} \varphi(\vec{r}) $ $\rightarrow$ $ \nabla \times \vec{v}_s = 0 $. (...
1
vote
2answers
88 views

vortex anti-vortex configuration to ground state [closed]

i'm studying kosterlitz transition. I'm reading this: https://assets.nobelprize.org/uploads/2018/06/advanced-physicsprize2016-1.pdf?_ga=2.51324009.1302372948.1538119052-1605759177.1538119052 Now ...
2
votes
1answer
57 views

Superfluidity: separation of quantised vortices in a vortex tangle

It is often quoted (see https://doi.org/10.1016/j.piutam.2013.09.008) that the separation $\delta$ between quantised vortices in a vortex tangle in a superfluid is approximately $$\delta \approx L^{-...
11
votes
1answer
325 views

Why are superfluid vortex lattices stable?

Both (a) neutral superfluids that are externally rotated, and (b) type-II superconductors (i.e. charged superfluids) under applied magnetic fields between the critical fields $h_{c1}$ and $h_{c2}$, ...
1
vote
1answer
88 views

Why do superfluid vortices form a lattice?

I often hear that in a superfluid, vortices get arranged in a lattice but I don't understand why and I've been hard pressed to find a discussion of it online. I'm aware that vortices should repel ...
2
votes
0answers
219 views

order of BKT phase transition

What is the order of the BKT phase transition (first or second), that is the phase transition in 2d in which thermal vortices destroy any order in the system. How is this connected to the "universal ...
2
votes
0answers
88 views

Why are quantum vortices so large?

Quantum vortices in helium are almost macroscopic, and can be be imaged in a light microscope: http://www.aps.org/units/dfd/pressroom/papers/gaff09.cfm How can vorticity be quantized on such a large ...
2
votes
2answers
278 views

Nomenclature clarification concerning solitons

My experience with solitons is restricted to the classical setting, namely solutions to the quartic interaction $\phi^4$, the Sine-Gordon equation, and Korteweg–de Vries equations. I was explicit to ...
2
votes
1answer
607 views

Complex valued energy

I'm working on a 2D He superfluid system with vortices. I was asked to calculate the kinetic energy of vortex-(anti-)vortex pairs and compare the two situations. One finds in literature that the ...