Anomaly of longitudinal spin susceptibility at superconducting instability inside a magnetic phase

Hiroyuki Yamase; Muhammad Zafur

doi:10.1103/physrevb.103.224527

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arXiv · 2103.02217

Anomaly of longitudinal spin susceptibility at superconducting instability inside a magnetic phase

Hiroyuki Yamase·Muhammad Zafur

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Abstract

We study the longitudinal spin susceptibility inside a magnetically ordered phase, which exhibits a superconducting instability leading to a coexistence of the two ordered phases. Inside the magnetic phase, the superconducting gap acquires a linear term in a magnetic field applied along the direction of the magnetic moment. We find that such a linear term generates a jump of the longitudinal spin susceptibility when the superconducting instability occurs via a continuous phase transition. This anomaly at the superconducting instability is a thermodynamic signature of the microscopic coexistence of superconductivity and magnetism, and can be a general feature associated with the breaking of spin rotational symmetry inside the magnetic phase.

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Hiroyuki Yamase, Muhammad Zafur. 2021-03-03. Anomaly of longitudinal spin susceptibility at superconducting instability inside a magnetic phase. https://doi.org/10.1103/physrevb.103.224527

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