Year: 2024
Type: article
Abstract: We present a theory for charge-4 e superconductivity as a leading low-temperature instability with a nontrivial d -wave symmetry. We show that in several microscopic models for the pair-density-wave (PDW) state, when the PDW wave vectors connect special parts of the Fermi surface, the predominant interaction is in the bosonic pairing channel mediated by exchanging low-energy fermions. This bosonic pairing interaction is repulsive in the s -wave channel but attractive in the d -wave one, leading to a d -wave charge-4 e superconductor. By analyzing the Ginzburg-Landau free energy including higher-order fluctuation effects of PDW, we find that the charge-4 e superconductivity emerges as a vestigial order of PDW, and sets in via a first-order transition. Both the gap amplitude and the transition temperature decay monotonically with increasing superfluid stiffness of the PDW order. Our work provides a microscopic mechanism of higher-charge condensates with unconventional ordering symmetry in strongly-correlated materials.
Source: npj Quantum Materials
Authors: Yi-Ming Wu, Yuxuan Wang
Institutions: Stanford University, University of Florida
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,790
OpenAlex ID: W4402273784