Author(s): Liu, WH (Liu, Wen-Hao); Luo, JW (Luo, Jun-Wei); Li, SS (Li, Shu-Shen); Wang, LW (Wang, Lin-Wang)

Source: PHYSICAL REVIEW B Volume: 105 Issue: 22 Article Number: 224306 DOI: 10.1103/PhysRevB.105.224306 Published: JUN 13 2022

Abstract: Ultrafast photoexcitation can induce a nonequilibrium dynamic with electron-lattice interaction, offering an effective way to study photoinduced phase transitions (PIPTs) in solids. The issue that atomic displacements after photoexcitation belong to a coherent change or disordered process has become controversial in the PIPT community. Using real-time, time-dependent density functional theory (rt-TDDFT) simulations, we obtained both the coherent and the disordered PIPTs (dimer dissociation) in IrTe2 with different electronic occupations. More importantly, we found that in the disordered phase transition there exists a local correlation between different dimers regarding their dissociation status. We define these Jr-Ir dimers directly connected by Te atoms, including intralayer and vertically across the layers, as a group (group I). Other Jr-Ir dimers separated by five Jr atoms from Jr-Ir dimers in group I are divided into another group (group II). The dimers in the same group will dissociate in a correlated fashion; they either all dissociate or all do not dissociate. On the other hand, the dimers in neighboring groups will have an anticorrelation: If the dimers in one group dissociate, the dimers in the neighboring group tend not to be dissociated, and vice versa.

Accession Number: WOS:000825152900004

ISSN: 2469-9950

eISSN: 2469-9969

Full Text: https://journals.aps.org/prb/abstract/10.1103/PhysRevB.105.224306