Low Temperature Physics

On the possibility of simultaneous spiral and superfluid ordering in a Fermi liquid

S. V. Peletminskiǐ, A. A. Yatsenko, S.N. Shulga

Published Mar 1, 2004• 1 citation

Abstract

A study is made of one of the possible forms of ordering of Fermi systems—superfluid spiral ordering, wherein not only the phase invariance of the state is broken but so are the translational invariance and the invariance with respect to spin rotations. A general method of studying superfluid spiral ordering is formulated on the basis of the Fermi-liquid approach to the consideration of superfluid states. For a one-component Fermi system we obtain the self-consistency equations for four order parameters and the temperature of the simultaneous phase transition to the superfluid and spiral states. The system of equations is investigated in the case of two nonzero order parameters. The transition temperature and the energy gap in the spectrum of elementary fermionic excitations are obtained as functions of the parameter of the spiral. The region of values of the spiral parameter in which the spiral superfluid ordering can exist is determined. The correlation function of the spins in the presence of spiral ordering is investigated.

DOI: 10.1063/1.1645176

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