Presentation Information
[24p-12N-4]Superconducting Diode Based on Asymmetric 3-JJs SQUID
〇Feng Li1, Masayuki Higashi1, Taichi Sato1, Masamitsu Tanaka1, Fujimaki Tanaka1 (1.Nagoya Univ.)
Keywords:
diode,phase shifter,3JJ SQUID
The superconducting diode effect can be induced when the asymmetric superconducting quantum interference (SQUID) is exposed to the magnetic field [1] or connected to a phase shifter [2]. An intrinsic phase shifter can be realized with a superconducting loop and a ferromagnetic π Josephson junction (π-JJ), providing an intrinsic phase bias φ (). The forward critical current , the backward resistance (Rsg) and diode efficiency are the important parameters for superconducting diode. Since is highly dependent on the critical currents of 0-JJs in the SQUID, the screening parameter () of SQUID will degrade the diode efficiency ().
We increased the number of 0-JJs in the SQUID to increase the value of of the superconducting diode while maintained the high diode efficiency. In the 3-JJs SQUID, the device asymmetry is not only related to the geometric inductance and Ic of 0-JJs, but also the intrinsic phase bias that applied to each SQUID loop (determined by the value of L1 and L2). In the preliminary experiment, the superconducting diode based on asymmetric configuration with 3-JJs (in parallel) in the SQUID has much larger (~ 450 μA) than that with 2-JJs SQUID (~ 210 μA), supposing with the same maximum Ic (~ 150 μA) in the devices. The superconducting diode based on asymmetric 3-JJs SQUID still has a diode efficiency up to 38%. We believe this result offers promising prospects for engineering the superconducting diode properties in the future.
We increased the number of 0-JJs in the SQUID to increase the value of of the superconducting diode while maintained the high diode efficiency. In the 3-JJs SQUID, the device asymmetry is not only related to the geometric inductance and Ic of 0-JJs, but also the intrinsic phase bias that applied to each SQUID loop (determined by the value of L1 and L2). In the preliminary experiment, the superconducting diode based on asymmetric configuration with 3-JJs (in parallel) in the SQUID has much larger (~ 450 μA) than that with 2-JJs SQUID (~ 210 μA), supposing with the same maximum Ic (~ 150 μA) in the devices. The superconducting diode based on asymmetric 3-JJs SQUID still has a diode efficiency up to 38%. We believe this result offers promising prospects for engineering the superconducting diode properties in the future.