Unusual superconducting isotope effect in the presence of a quantum criticality
Abstract
The isotope effect in superconductivity (SC) is used to make a concrete connection to a quantum critical point (QCP) that is tunable by isotopic mass substitution. We find a distinct contribution to the isotope exponent in SC and derive an explicit relation to the critical exponent of a QCP. The relation between the two exponents is general and can be used as an experimental signature for the connection between SC and a QCP. We demonstrate it 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.
- Publication:
-
Physical Review B
- Pub Date:
- May 2016
- DOI:
- 10.1103/PhysRevB.93.184507
- arXiv:
- arXiv:1602.00437
- Bibcode:
- 2016PhRvB..93r4507K
- Keywords:
-
- Condensed Matter - Superconductivity;
- Condensed Matter - Statistical Mechanics
- E-Print:
- Phys. Rev. B 93, 184507 (2016)