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arXiv · 2605.22292

Equilibrium Stabilization of a Hidden Phase Like Metallic State in 1T-TaS2

Turgut Yilmaz·Anil Rajapitamahuni·Suji Park·Houk Jang·Asish K. Kundu·Elio Vescovo
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Abstract

Electronic phases that lie outside the equilibrium ground state offer a route to explore competing configurations in correlated materials. In 1T-TaS2, ultrafast excitation accesses a metallic hidden phase that is distinct from the commensurate insulating ground state. Here we use angle-resolved photoemission spectroscopy to show that an equivalent electronic configuration is stabilized in exfoliated intermediate-thickness 1T-TaS2 flakes, where it persists up to room temperature before evolving through a different sequence of electronic transitions. This equilibrium hidden-phase-like state hosts a metallic band with finite Fermi-level spectral weight while retaining the characteristic hybridization gaps associated with the star-of-David band folding. These results establish a platform for controlling competing electronic states in layered materials, with implications for both quantum science and phase change technologies.

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Turgut Yilmaz, Anil Rajapitamahuni, Suji Park, Houk Jang, Asish K. Kundu, Elio Vescovo. 2026-05-21. Equilibrium Stabilization of a Hidden Phase Like Metallic State in 1T-TaS2. https://arxiv.org/abs/2605.22292

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