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arXiv · 1611.04541

Probing the pairing interaction and multiple Bardasis-Schrieffer modes using Raman spectroscopy

S. Maiti·T. A. Maier·T. Boehm·R. Hackl·P. J. Hirschfeld
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Abstract

In unconventional superconductors, understanding the form of the pairing interaction is the primary goal. In this regard, Raman spectroscopy is a very useful tool, as it identifies the ground state and also the subleading pairing channels by probing collective modes. Here we propose a general theory for multiband Raman response and identify new features in the spectrum that can provide a robust test for a pairing theory. We identify multiple Bardasis-Schrieffer type collective modes and connect the weights of these modes to the sub-leading gap structures within a microscopic pairing theory. The conclusions are completely general, and we apply our approach to interpret the B1g Raman scattering in hole-doped BaFe2As2.

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S. Maiti, T. A. Maier, T. Boehm, R. Hackl, P. J. Hirschfeld. 2016-11-14. Probing the pairing interaction and multiple Bardasis-Schrieffer modes using Raman spectroscopy. https://doi.org/10.1103/physrevlett.117.257001

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