2024, Pressure-Driven Layer-dependent Phase Transitions and Enhanced Interlayer Coupling in PdSe2 Crystals, Nano Research.
2024, Pressure-Driven Layer-dependent Phase Transitions and Enhanced Interlayer Coupling in PdSe2 Crystals, Nano Research.
Abstract:
Pressure exerts a profound influence on atomic configurations and interlayer interactions, thereby modulating the electronic and structural properties of materials. While high pressure has been observed to induce a structural phase transition in bulk PdSe2 crystals, leading to a transition from semiconductor to metal, the high-pressure behavior of few-layer PdSe2 remains elusive. Here, employing diamond anvil cell (DAC) techniques and high-pressure Raman spectroscopy, we investigate the structural evolution of layer-dependent PdSe2 under high pressure. We reveal that pressure significantly enhances interlayer coupling in PdSe2, driving structural phase transitions from an orthorhombic to a cubic phase. We demonstrate that PdSe2 crystals exhibit distinct layer-dependent pressure thresholds during the phase transition, with the decrease of transition pressure as the thickness of PdSe2 increases. Furthermore, our results of polarized Raman spectra confirm a reduction in material anisotropy with increasing pressure. This study offers crucial insights into the structural evolution of layer-dependent van der Waals materials under pressure, advancing our understanding of their pressure-induced behaviors.
Keywords: Palladium diselenide, High pressure, Phase transition, Diamond anvil cell, Anisotropy.
Link: https://link.springer.com/article/10.1007/s12274-024-6927-4
