Odd-Parity Pairing Superconductivity under Tetragonal Symmetry -Possible Application to Sr_<b>2</b>RuO_<b>4</b>-

Abstract

The odd-parity pairing states are classified group-theoretically under tetragonal symmetry and characterized when the spin-orbit coupling is weak. The classified states include higher orbital angular momentum p , f , … -wave pairing. In connection with a layered perovskite superconductor, Sr 2 RuO 4 , prominent physical properties of the non-unitary state such as the spontaneous moment, large residual density of states and the spontaneous lattice distortion are highlighted to help to distinguish it from other triplet and singlet states.