Superconductivity in Weyl semimetal Mo<sub>x</sub>W<sub>1-x</sub>Te<sub>2</sub> driven by high pressure
ORAL
Abstract
Tungsten ditelluride and molybdenum ditelluride have attracted tremendous attention due to recent discoveries of the Weyl semimetal state, large unsaturated magnetoresistance, and superconductivity in these materials. MoxW1-xTe2 is reported to be a Weyl semimetal with x = 0.25 and Weyl semimetal states are also predicted to exist in other doping. We carried out systematic high pressure measurements on MoxW1-xTe2 single crystals with doping via homemade BeCu clamp cells. High-quality single crystals of MoxW1-xTe2, with x = 0.25, 0.60, 0.90, were grown by chemical vapor transport method which were then characterized by X-ray diffraction and energy dispersive X-ray spectroscopy. In Mo0.25W0.75Te2, a structural transition was observed under pressure 12.3 kbar with no signature of superconductivity at temperature down to 1.3 K and under pressure up to 17 kbar. In Mo0.60W0.40Te2 and Mo0.90W0.10Te2, structural transitions were observed at ambient pressure. Superconductivity appears in Mo0.60W0.40Te2 with an onset Tc of 1.7 K under 8.4 kbar and in Mo0.90W0.10Te2 with an onset Tc of 1.4 K under 3.9 kbar. Tc continuously increases as pressure increases up to 17 kbar, the highest pressure we applied. Measurements under higher pressure range using diamond anvil cells are in progress.
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Presenters
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Rabin Dahal
- Texas Center for Superconductivity and Department of Physics, University of Houston, Houston TX 77204
- Texas Center for Superconductivity and Department of Physics, University of Houston, Houston, TX 77204, USA