Coexistence of superconductivity and sliding polar metal state in HgPSe3

TL;DR

This paper reports the discovery of HgPSe3 as a bulk polar metal that exhibits superconductivity at low temperatures, demonstrating a rare coexistence of polarity and metallicity stabilized by pressure.

Contribution

It introduces HgPSe3 as a new bulk polar metal with superconductivity, revealing a pressure-stabilized chiral structure and a novel interlayer sliding mechanism for coexistence of properties.

Findings

HgPSe3 is a robust bulk polar metal at room temperature.

Superconductivity with Tc up to 11 K observed in HgPSe3.

Pressure stabilizes the chiral polar metallic state.

Abstract

The simultaneous presence of polarity and metallicity in a material signifies an exotic polar metal state, but such materials are extremely rare, especially in bulk form, due to mutually exclusive nature of the fundamental defining properties. Here, we report experimental findings that HgPSe3 is a robust bulk polar metal at room temperature with a chiral structure stabilized by pressure and, remarkably, this polar metal hosts superconductivity with critical temperature Tc up to 11 K. Theoretical analysis reveals a two-step interlayer sliding-then-compressing mechanism for coexistence of polarity and metallicity in HgPSe3. This work unveils a new paradigm for creating the bulk polar metal state and simultaneous presence of coexisting quantum orders, raising the prospect of discovering novel emergent physics using pressure as a tuning knob.