Optimized Superconductivity in the Vicinity of a Nematic Quantum Critical Point in the Kagome Superconductor Cs(VTi)Sb

Overview

Journal Nat Commun

Specialty Biology

Date 2023 Jul 6

PMID 37414793

Authors

Yeahan Sur

Kwang-Tak Kim

Sukho Kim

Kee Hoon Kim

Affiliations

Soon will be listed here.

Abstract

CsVSb exhibits superconductivity at T = 3.2 K after undergoing intriguing two high-temperature transitions: charge density wave order at ~98 K and electronic nematic order at T ~ 35 K. Here, we investigate nematic susceptibility in single crystals of Cs(VTi)Sb (x = 0.00-0.06) where double-dome-shaped superconducting phase diagram is realized. The nematic susceptibility typically exhibits the Curie‒Weiss behaviour above T, which is monotonically decreased with x. Moreover, the Curie‒Weiss temperature is systematically suppressed from ~30 K for x = 0 to ~4 K for x = 0.0075, resulting in a sign change at x = ~0.009. Furthermore, the Curie constant reaches a maximum at x = 0.01, suggesting drastically enhanced nematic susceptibility near a putative nematic quantum critical point (NQCP) at x = ~0.009. Strikingly, T is enhanced up to ~4.1 K with full Meissner shielding realized at x = ~0.0075-0.01, forming the first superconducting dome near the NQCP. Our findings directly point to a vital role of nematic fluctuations in enhancing the superconducting properties of Cs(VTi)Sb.

Citing Articles

Optimized superconductivity in the vicinity of a nematic quantum critical point in the kagome superconductor Cs(VTi)Sb.

Sur Y, Kim K, Kim S, Kim K Nat Commun. 2023; 14(1):3899.

PMID: 37414793 PMC: 10326258. DOI: 10.1038/s41467-023-39495-1.

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