Strain tuned structural phase transitions and optical switching in 1T-ZrS2 and 1T-ZrSe2

by Edoardo Martino (École polytechnique fédérale de Lausanne)

Wednesday 6 Nov 2019, 16:30 → 17:15 Europe/Rome

Aula Conversi (Dip. di Fisica - Edificio G. Marconi)

Strain is a versatile and powerful tool to manipulate electronic properties of 2D materials as transition metal dichalcogenides. We found strain-induced structural phase transitions in 1T-ZrS2 and 1T-ZrSe2. High-pressure Raman spectroscopy and optical absorption experiments revealed a reversible metallization of 1T-ZrSe2 at 8 GPa and an irreversible transformation of 1T-ZrS2 to a new semiconducting phase at 3 GPa, with smaller band gap (from 1.7 to 0.7 eV). The study is complemented by structural investigation under pressure and ab initio band structure calculations. Strain-tuned transitions in 2D materials pave the way for the realization of new devices, as strain-patterned homojunctions.