High-temperature Josephson diode

Sanat Ghosh; Vilas Patil; Amit Basu; Kuldeep; Achintya Dutta; Digambar A. Jangade; Ruta Kulkarni; A. Thamizhavel; Jacob F. Steiner; Felix von Oppen; Mandar M. Deshmukh

doi:10.1038/s41563-024-01804-4

arXiv · 2210.11256

High-temperature Josephson diode

Sanat Ghosh·Vilas Patil·Amit Basu·Kuldeep·Achintya Dutta·Digambar A. Jangade·Ruta Kulkarni·A. Thamizhavel·Jacob F. Steiner·Felix von Oppen·Mandar M. Deshmukh

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Abstract

Symmetry plays a critical role in determining various properties of a material. Semiconducting p-n junction diode exemplifies the engineered skew electronic response and is at the heart of contemporary electronic circuits. The non-reciprocal charge transport in a diode arises from doping-induced breaking of inversion symmetry. Breaking of time-reversal, in addition to inversion symmetry in some superconducting systems, leads to an analogous device - the superconducting diode. Following the pioneering first demonstration of the superconducting diode effect (SDE), a plethora of new systems showing similar effects have been reported. SDE lays the foundation for realizing ultra-low dissipative circuits, while Josephson phenomena-based diode effect (JDE) can enable realization of protected qubits. However, SDE and JDE reported thus far are at low temperatures ($\sim$ 4 K or lower) and impede their adaptation to technological applications. Here we demonstrate a Josephson diode working up to 77 K using an artificial Josephson junction (AJJ) of twisted layers of Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ (BSCCO). The non-reciprocal response manifests as an asymmetry in the magnitude of switching currents and their distributions and appears for all twist angles. The asymmetry is induced by and tunable with a very small magnetic field applied perpendicular to the junction. We report a record asymmetry of 60 % at 20 K. We explain our results within a vortex-based scenario. Our results provide a path toward realizing superconducting quantum circuits at liquid nitrogen temperature.

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cond-mat.supr-con cond-mat.mes-hall cond-mat.mtrl-sci cond-mat.str-el

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Sanat Ghosh, Vilas Patil, Amit Basu, Kuldeep, Achintya Dutta, Digambar A. Jangade, Ruta Kulkarni, A. Thamizhavel, Jacob F. Steiner, Felix von Oppen, Mandar M. Deshmukh. 2022-10-20. High-temperature Josephson diode. https://doi.org/10.1038/s41563-024-01804-4

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