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arXiv · 2111.13480

Dynamic short-range correlation in photoinduced disorder phase transitions

Wen-Hao Liu·Jun-Wei Luo·Shu-Shen Li·Lin-Wang Wang
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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 coherent change or disordered process, has become a controversy in the PIPT community. Using real-time time-dependent density functional theory (rt-TDDFT) simulations, we obtain both the coherent and the disordered PIPTs (dimer dissociation) in IrTe2 with the 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. One can define vertical groups across the layers. The dimers in the same group will dissociate in a correlated fashion: they either all dissociate, or all not dissociate. On the other hand, the dimers in neighboring groups will have an anti-correlation: if the dimers in one group dissociate, the dimers in the neighboring group tend not to be dissociated, and vice versus.

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Wen-Hao Liu, Jun-Wei Luo, Shu-Shen Li, Lin-Wang Wang. 2021-11-26. Dynamic short-range correlation in photoinduced disorder phase transitions. https://doi.org/10.1103/physrevb.105.224306

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