Non-equilibrium photoexcited carrier effects in a graphene-based Josephson junction

作者：Tsumura Kohei^*; Furukawa Naoki; Ito Hironori; Watanabe Eiichiro; Tsuya Daiju; Takayanagi Hideaki

来源：Applied Physics Letters, 2016, 108(3): 033109.

DOI：10.1063/1.4940377

We studied the superconducting proximity effect under photoexcitation by illuminating a superconductor/monolayer graphene/superconductor (SGS) Josephson junction with monochromatic light at a wavelength of 1.31 mu m. Although the critical current I-c can be controlled by the irradiation power P, its variation cannot be explained by modification of the carrier density, which has been reported for semiconductor- based Josephson junctions. The estimated electron temperature of graphene is proportional to P-delta, where delta similar or equal to 1/3. This relation clearly indicates that photogenerated non-equilibrium carrier dynamics are responsible for the variation of Ic with P. We suggest that the SGS junction can directly mediate interactions between the optical field and the superconducting state.

• 出版日期2016-1-18