Universal zero-frequency Raman slope in a d-wave superconductor

Abstract

It is known that for an unconventional superconductor with nodes in the gap, the in-plane microwave or dc conductivity saturates at low temperatures to a universal value independent of the impurity concentration. We demonstrate that a similar feature can be accessed using channel-dependent Raman scattering. It is found that, for a $d_{x^2-y^2}$-wave superconductor, the slope of low-temperature Raman intensity at zero frequency is universal in the $A_{1g}$ and $B_{2g}$ channels, but not in the $B_{1g}$ channel. Moreover, as opposed to the microwave conductivity, universal Raman slopes are sensitive not only to the existence of a node, but also to different pairing states and should allow one to distinguish between such pairing states.

5 pages

References in corpus (2)

• Universal Heat Conduction in YBa_2Cu_3O_6.9
• Raman Scattering in Cuprate Superconductors

Cited by in corpus (5)

• Inelastic Light Scattering From Correlated Electrons
• Optical symmetries and anisotropic transport in high-Tc superconductors
• Effect of anisotropy on universal transport in unconventional superconductors
• Response, relaxation and transport in unconventional superconductors
• Electronic Raman scattering in superconductors on triangle lattices