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arXiv · 1602.00437

An unusual superconducting Isotope Effect in the presence of a Quantum Criticality

Yaron Kedem·Jian-Xin Zhu·Alexander V. Balatsky
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Abstract

We discuss the possible connection between superconductivity (SC) and quantum critical points (QCP) for any QCP that is tunable by isotopic mass substitution. We find a distinct contribution to the isotope exponent, due to the proximity to a QCP, which can be used as an experimental signature for the relation between SC and QCP. The relation is demonstrated in a scenario where the SC pairing is due to modes related to a structural instability. Within this model the isotope exponent is derived in terms of microscopic parameters.

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Yaron Kedem, Jian-Xin Zhu, Alexander V. Balatsky. 2016-02-01. An unusual superconducting Isotope Effect in the presence of a Quantum Criticality. https://doi.org/10.1103/physrevb.93.184507

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