Abstract
We present a systematic high-pressure study of layered van der Waals semiconductor GaTe through electrical transport, photoluminescence, and Raman spectroscopy measurements. We report observation of pressure-induced metallization and superconductivity (SC) in GaTe simultaneously occurring at ∼3 GPa, with an onset superconducting critical temperature of . Analysis shows that a quasi–two-dimensional to three-dimensional structural crossover plays a crucial role in driving the observed metallization and SC. Upon further compression, first decreases gradually and then begins to increase above ∼10 GPa, displaying a V-shaped feature (SC-I→SC-II) due to a structural transition (). After reaching a local maximum of 4.5 K at ∼18 GPa, remains almost unchanged up to a highest pressure of 48.1 GPa. A comparison of the upper critical fields at different pressures spanning the SC-I and SC-II phases reveals that their pairing mechanisms may be different from each other. These results demonstrate that the band gap of layered semiconductor GaTe is highly tunable, which may stimulate further investigations by strain engineering, intercalation, and electrostatic doping.
- Received 15 December 2022
- Revised 17 January 2023
- Accepted 19 January 2023
DOI:https://doi.org/10.1103/PhysRevB.107.024512
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