Pressure-induced metallization and superconducting phase in ReS 2

Abstract

High-pressure physics: transitions and superconductivity of compressed ReS2 ReS2 is a unique transition metal dichalcogenide (TMD) in terms of its distorted low-symmetry structure at ambient conditions. A subject that remains elusive so far is how its structure and electronic properties respond to pressure. Now a collaborative team led by Prof. Jian Sun from Nanjing University looks at the phase transitions in ReS2 under pressure utilizing ab initio crystal structure searching combining with high-pressure electrical resistance measurements. Upon small compression, the ambient phase transforms to a triclinic distorted 1T structure before changing to a tetragonal polymorph at higher pressure. The former transition is due to the layer sliding with a Peierls mechanism governing the energy stabilization and this semiconducting phase would be metallized with increasing pressure. The latter predicted structure is superconducting at a critical temperature of around 2 K at 100 GPa. This work suggests the role of pressure in tailoring the electronic structures of TMDs.