Strong enhancement of superconductivity at high pressures within the charge-density-wave states of 2H-TaS 2 and 2H-TaSe 2

  title={Strong enhancement of superconductivity at high pressures within the charge-density-wave states of 2H-TaS 2 and 2H-TaSe 2},
  author={D. Freitas and P. Rodi{\`e}re and M. R. Osorio and E. Navarro-Moratalla and N. Nemes and V. Tissen and L. Cario and E. Coronado and M. Garc'ia-Hern'andez and S. Vieira and M. N'unez-Regueiro and H. Suderow},
  journal={Physical Review B},
We present measurements of the superconducting and charge density wave critical temperatures (Tc and TCDW) as a function of pressure in the transition metal dichalchogenides 2H-TaSe2 and 2H-TaS2. Resistance and susceptibility measurements show that Tc increases from temperatures below 1 K up to 8.5 K at 9.5 GPa in 2H-TaS2 and 8.2 K at 23 GPa in 2H-TaSe2. We observe a kink in the pressure dependence of TCDW at about 4 GPa that we attribute to the lock-in transition from incommensurate CDW to… Expand

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