2D van der Waals superconducting devices for science and technology

2Dvan der Waals superconducting devices for science and technology

Mandar M. Deshmukh

Tata Institute of Fundamental Research,India

Over the last decade, the development ofJosephson devices based on van der Waals (vdW) materials has advanced rapidly,representing a paradigm shift driven by the advent of 2D materials. The diversevdW materials library, combined with advanced fabrication techniques, enablesthe integration of materials with vastly disparate properties for scientificexploration. vdW Josephson junctions (JJs) offer a unique route to explorenovel functionalities and associated physics that remain inaccessible in conventionalJJs, which have reached an industrial level of fabrication. Beyond materialdiversity, vdW materials offer fundamental new control over device symmetriesand enable the realization of Hamiltonians unique to 2D systems.

After a broad introduction, I will discusstwo classes of materials and devices. First, proximitized graphene-basedJosephson junctions that are gate tunable. The graphene Josephson FET enables aquantum-noise-limited parametric amplifier with performance comparable to thebest discrete amplifiers in this class [1]. One can realize extremely sensitiveand fast bolometers [2] – useful for dark matter search, among otherapplications. Second, twisted van der Waals heterostructures based on thehigh-temperature superconductor Bi2Sr2CaCu2O8+δ enable the realization of ahigh-temperature Josephson diode [3] for the first time. Such Josephson diodesoffer an opportunity to realize new devices at liquid nitrogen temperatures.

While opportunities abound with vdW JJs,the challenge of scalability must be overcome to translate them into real-worlddevices.

[1] "Quantum-noise-limited microwaveamplification using a graphene Josephson junction" Joydip Sarkar et al. , Nature Nanotechnology 17, 1147 (2022).

[2] “ Kerr non-linearity enhances theresponse of a graphene Josephson bolometer,” Sarkar et al. ,  NatureCommunications volume 16, 7043 (2025).

[3] "High-temperature Josephsondiode," Sanat Ghosh et al. Nature Materials 23, 612 (2024).