Nonmonotonic Temperature-Dependent Dissipation at Nonequilibrium in Atomically Thin Clean-Limit Superconductors

Nano Letters, vol. 21, pp. 583–589

Abstract

Resistance in superconductors arises from the motion of vortices driven by flowing supercurrents or external electromagnetic fields and may be strongly affected by thermal or quantum fluctuations. The common expectation is that as the temperature is lowered, vortex motion is suppressed, leading to a decreased resistance. We show experimentally that in clean-limit atomically thin 2H-NbSe 2 the resistance below the superconducting transition temperature may be nonmonotonic, passing through a minimum before increasing again as the temperature is decreased further. The effect is most pronounced in monolayer devices and cannot be understood in terms of known mechanisms. We propose a qualitative two-fluid vortex model in which thermal fluctuations of pinned vortices control the mobility of the free vortices. The findings provide a new perspective on fundamental questions of vortex mobility and dissipation in superconductors.

Authors 9

1. Avishai Benyamini corresponding

   Columbia University

   Affiliation as printed

   Department of Mechanical Engineering, Columbia University, New York, New York 10027, United States

2. Dante Marvin Kennes Aachen Institut für Theorie der Statistischen Physik

   Jülich Aachen Research Alliance · RWTH Aachen University

   Affiliation as printed

   Institut für Theorie der Statistischen Physik, RWTH Aachen University and JARA-Fundamentals of Future Information Technology, 52056 Aachen, Germany

3. Evan J. Telford

   Columbia University

   Affiliation as printed

   Department of Physics, Columbia University, New York, New York 10027, United States

4. Kenji Watanabe

   National Institute for Materials Science

   Affiliation as printed

   National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan

5. Takashi Taniguchi

   National Institute for Materials Science

   Affiliation as printed

   National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan

6. Andrew J. Millis

   Columbia University

   Affiliation as printed

   Department of Physics, Columbia University, New York, New York 10027, United States

7. James Hone

   Columbia University

   Affiliation as printed

   Department of Mechanical Engineering, Columbia University, New York, New York 10027, United States

8. Cory R. Dean

   Columbia University

   Affiliation as printed

   Department of Physics, Columbia University, New York, New York 10027, United States

9. Abhay N. Pasupathy

   Columbia University

   Affiliation as printed

   Department of Physics, Columbia University, New York, New York 10027, United States