TY - JOUR

T1 - Spontaneous rotational symmetry breaking and roton like excitations in gauged σ-model at finite density

AU - Gusynin, V. P.

AU - Miransky, V. A.

AU - Shovkovy, Igor

N1 - Funding Information:
V.P.G. and V.A.M. are grateful for support from the Natural Sciences and Engineering Research Council of Canada. The work of V.P.G. was supported also by the SCOPES-projects 7UKPJ062150.00/1 and 7 IP 062607 of the Swiss NSF. The work of I.A.S. was supported by Gesellschaft für Schwerionenforschung (GSI) and by Bundesministerium für Bildung und Forschung (BMBF).

PY - 2004/2/12

Y1 - 2004/2/12

N2 - The linear σ-model with a chemical potential for hypercharge is a toy model for the description of the dynamics of the kaon condensate in high density QCD. We analyze the dynamics of the gauged version of this model. It is shown that spontaneous breakdown of SU(2) × U(1)Y symmetry, caused by the chemical potential, is always accompanied by spontaneous breakdown of both rotational symmetry and electromagnetic U(1)em. The spectrum of excitations in this model is rich and, because of rotational symmetry breakdown, anisotropic. It is shown that there exist excitation branches that behave as phonon like quasiparticles for small momenta and as roton like ones for large momenta. This suggests that this model can be relevant for anisotropic superfluid systems.

AB - The linear σ-model with a chemical potential for hypercharge is a toy model for the description of the dynamics of the kaon condensate in high density QCD. We analyze the dynamics of the gauged version of this model. It is shown that spontaneous breakdown of SU(2) × U(1)Y symmetry, caused by the chemical potential, is always accompanied by spontaneous breakdown of both rotational symmetry and electromagnetic U(1)em. The spectrum of excitations in this model is rich and, because of rotational symmetry breakdown, anisotropic. It is shown that there exist excitation branches that behave as phonon like quasiparticles for small momenta and as roton like ones for large momenta. This suggests that this model can be relevant for anisotropic superfluid systems.

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U2 - 10.1016/j.physletb.2003.11.042

DO - 10.1016/j.physletb.2003.11.042

M3 - Article

AN - SCOPUS:1642472930

VL - 581

SP - 82

EP - 92

JO - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

JF - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

SN - 0370-2693

IS - 1-2

ER -