Pressure-driven layer-dependent phase transitions and enhanced interlayer coupling in PdSe_(2) crystals  

作　　者：Junnan Ding Xing Xie Xinyu Ouyang Junying Chen Fangping Ouyang Zongwen Liu Jian-Tao Wang Jun He Yanping Liu 

机构地区：[1]Institute of Quantum Physics, School of Physics, Central South University, Changsha, 410083, China [2]State Key Laboratory of Precision Manufacturing for Extreme Service Performance, Central South University, Changsha, 410083, China [3]School of Physics and Technology, State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources, Xinjiang University, Urumqi, 830046, China [4]School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, NSW, 2006, Australia [5]The University of Sydney Nano Institute, The University of Sydney, Sydney, NSW, 2006, Australia [6]Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China [7]School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China [8]Songshan Lake Materials Laboratory, Dongguan, 523808, China

出　　处：《Nano Research》2024年第11期10170-10178,共9页纳米研究（英文版）

基　　金：the financial support received from various entities,including the National Natural Science Foundation of China(No.52373311);the Key Program of the Science and Technology Department of Hunan Province(Nos.2019XK2001 and 2020XK2001);the Key Project of the Natural Science Program of Xinjiang Uygur Autonomous Region(No.2023D01D03);They also appreciate the support from the High-Performance Complex Manufacturing Key State Lab Project at Central South University(No.ZZYJKT2020-12);Z.W.L.extends thanks to the Australian Research Council(ARC Discovery Project,DP180102976)for their support;J.-T.W.acknowledges funding from the National Natural Science Foundation of China(Nos.92263202 and 12374020);the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB33000000);the National Key Research and Development Program of China(No.2020YFA0711502)。

摘　　要：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 PdSe_(2) crystals, leading to a transition from semiconductor to metal, the high-pressure behavior of few-layer PdSe_(2) remains elusive. Here, employing diamond anvil cell (DAC) techniques and high-pressure Raman spectroscopy, we investigate the structural evolution of layer-dependent PdSe_(2) under high pressure. We reveal that pressure significantly enhances interlayer coupling in PdSe_(2), driving structural phase transitions from an orthorhombic to a cubic phase. We demonstrate that PdSe_(2) crystals exhibit distinct layer-dependent pressure thresholds during the phase transition, with the decrease of transition pressure as the thickness of PdSe_(2) 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.

关 键 词：palladium diselenide high pressure phase transition diamond anvil cell ANISOTROPY 

分 类 号：TN32[电子电信—物理电子学]