[16p-B414-1~16] 17.3 Layered materials

▲ [16p-B414-10] Gate Defined Josephson junctions in monolayer WTe₂

Randle Michael¹, Masayuki Hosoda², Russell Deacon¹, Manabu Ohtomo², Kenji Watanabe³, Takashi Taniguchi³, Shota Okazaki⁴, Takao Sasagawa⁴, Kenichi Kawaguchi², Shintaro Sato², 〇Koji Ishibashi¹ (1.RIKEN, 2.Fujitsu, 3.NIMS, 4.TIT)

Keywords:Josephson junction, 2D material

Josephson junctions have been fabricated in the monolayer WTe₂. Contacts to the WTe₂ layer are formed with the in-situ etching and sputtering of Pd/NbTi. Superconductivity is induced in the WTe₂ layer by applying positive gate voltages on the left and right side gates, and is controlled by the center gate. Formation of the Josephson junction is confirmed by the quantized steps in the current-voltage characteristics (Schapiro steps) under the microwave irradiation and magnetic field response of the supercurrent. It is found that the current channel is not uniform in the junction and the screening is lacking in the superconducting leads in the WTe₂ region.