arXiv:2010.11956 · Physical review. B./Physical review. B

Anatomy of Z2 fluxes in anyon Fermi liquids and Bose condensates

Óscar Pozo, Peng Rao, Chuan Chen, Inti Sodemann

Published Jan 28, 2021• 8 citations

Abstract

We study in detail the properties of $\ensuremath{\pi}$ fluxes embedded in a state with a finite density of anyons that form either a Fermi liquid or a Bose-Einstein condensate. By employing a recently developed exact lattice bosonization in 2D, we demonstrate that such $\ensuremath{\pi}$ flux remains a fully deconfined quasiparticle with a finite energy cost in a Fermi liquid of emergent fermions coupled to a ${\mathbb{Z}}_{2}$ gauge field. This $\ensuremath{\pi}$ flux is accompanied by a screening cloud of fermions, which in the case of a Fermi gas with a parabolic dispersion binds exactly $1/8$ of a fermionic hole. In addition, there is a long-ranged power-law oscillatory disturbance of the liquid surrounding the $\ensuremath{\pi}$ flux akin to Friedel oscillations. These results carry over directly to the $\ensuremath{\pi}$ flux excitations in orthogonal metals. In sharp contrast, when the $\ensuremath{\pi}$ flux is surrounded by a Bose-Einstein condensate of particles coupled to a ${\mathbb{Z}}_{2}$ gauge field, it binds a superfluid half-vortex, becoming a marginally confined excitation with a logarithmic energy cost divergence.

DOI: 10.1103/physrevb.103.035145

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arXiv:2010.11956 · Physical review. B./Physical review. B

Anatomy of Z2 fluxes in anyon Fermi liquids and Bose condensates

Óscar Pozo, Peng Rao, Chuan Chen, Inti Sodemann

Published Jan 28, 2021• 8 citations

arXiv HTML PDF

Abstract

We study in detail the properties of

\ensuremath{\pi}

fluxes embedded in a state with a finite density of anyons that form either a Fermi liquid or a Bose-Einstein condensate. By employing a recently developed exact lattice bosonization in 2D, we demonstrate that such

\ensuremath{\pi}

flux remains a fully deconfined quasiparticle with a finite energy cost in a Fermi liquid of emergent fermions coupled to a

{\mathbb{Z}}_{2}

gauge field. This

\ensuremath{\pi}

flux is accompanied by a screening cloud of fermions, which in the case of a Fermi gas with a parabolic dispersion binds exactly

1/8

of a fermionic hole. In addition, there is a long-ranged power-law oscillatory disturbance of the liquid surrounding the

\ensuremath{\pi}

flux akin to Friedel oscillations. These results carry over directly to the

\ensuremath{\pi}

flux excitations in orthogonal metals. In sharp contrast, when the

\ensuremath{\pi}

flux is surrounded by a Bose-Einstein condensate of particles coupled to a

{\mathbb{Z}}_{2}

gauge field, it binds a superfluid half-vortex, becoming a marginally confined excitation with a logarithmic energy cost divergence.

DOI: 10.1103/physrevb.103.035145

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Vortex patterns in the almost-bosonic anyon gas

Michele Correggi, Romain Duboscq, Douglas Lundholm +1 more

Jan 29, 201910 citations

Vortex patterns in the almost-bosonic anyon gas

Michele Correggi, Romain Duboscq, Douglas Lundholm +1 more

arXiv:1901.10739Europhysics Letters (EPL)Jun 7, 201922 citations

We study in detail the properties of

\ensuremath{\pi}

\ensuremath{\pi}

flux remains a fully deconfined quasiparticle with a finite energy cost in a Fermi liquid of emergent fermions coupled to a

{\mathbb{Z}}_{2}

gauge field. This

\ensuremath{\pi}

flux is accompanied by a screening cloud of fermions, which in the case of a Fermi gas with a parabolic dispersion binds exactly

1/8

of a fermionic hole. In addition, there is a long-ranged power-law oscillatory disturbance of the liquid surrounding the

\ensuremath{\pi}

flux akin to Friedel oscillations. These results carry over directly to the

\ensuremath{\pi}

flux excitations in orthogonal metals. In sharp contrast, when the

\ensuremath{\pi}

flux is surrounded by a Bose-Einstein condensate of particles coupled to a

{\mathbb{Z}}_{2}

gauge field, it binds a superfluid half-vortex, becoming a marginally confined excitation with a logarithmic energy cost divergence.

n_0/n\ll 1

that is used as a small parameter---unlike in the Bogolyubov theory for a quasi-ideal Bose gas, in which the small parameter is the ratio of the number of supracondensate excitations to the number of particles in an intensive BEC,

(n-n_0)/n_0\ll 1

. A closed system of nonlinear integral equations for the normal and anomalous self-energy parts is obtained, in the framework of a renormalized perturbation theory built on combined hydrodynamic and field variables. In the framework of the hard-spheres model, a spectrum of quasiparticles is obtained, which is in good accordance with the experimental spectrum of elementary excitations in superfluid

^4

He. The question of applicability of the Landau criterion in the absence of quantum vortices is discussed.

T^ * \propto \sqrt B

. The behavior of Fermi systems that approach FCQPT from the disordered phase is considered. This behavior can be viewed as a highly correlated one, because the effective mass is large and strongly depends on the density. We expect that FCQPT takes place in trapped Fermi gases and in low-density neutron matter, leading to stabilization of the matter by lowering its ground-state energy. When the system recedes from FCQPT, the effective mass becomes density independent and the system is suited perfectly to be conventional Landau Fermi liquid.