Using controlled disorder to probe the interplay between charge order and superconductivity in 2<i>H</i>-NbSe<sub>2</sub>
ORAL
Abstract
The interplay between superconductivity and charge density wave (CDW) in single crystals of 2H-NbSe2 was probed by tuning the amount of point - like disorder induced by 2.5 MeV electron irradiation. With increasing dose, Tc shows $non-trivial$ behavior, first increasing from 7.25 K to 7.45 K and then decreasing to 7.3 K, whereas TCDW monotonically decreases from 33 K and becomes unresolvable below 27 K. At this dose, Tc has a sharp drop by 0.3 K. The low temperature variation of the London penetration depth shows robust exponential behavior suggesting nodeless order parameter before and after irradiation, and overall trend is consistent with multiband superconductivity with two effective superconducting gaps. Our result supports the scenario of complex interplay of CDW and superconductivity, - competition for the density of states, but possible softening of the phon modes by long - range CDW.
*This work was supported by the US DOE, Office of Science, BES Materials Science and Engineering Division under contract # DE-AC02-07CH11358.
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Presenters
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Kyuil Cho
- Ames Laboratory and Department of Physics & Astronomy, Iowa State University
- Ames Laboratory
- Ames Laboratory and Iowa state University