לוח שנה משולב

Over the last decade, the development of Josephson devices based on van der Waals (vdW) materials has advanced rapidly, representing a paradigm shift driven by the advent of 2D materials. The diverse vdW materials library, combined with advanced fabrication techniques, enables the integration of materials with vastly disparate properties for scientific exploration. vdW Josephson junctions (JJs) offer a unique route to explore novel functionalities and associated physics that remain inaccessible in conventional JJs, which have reached an industrial level of fabrication. Beyond material diversity, vdW materials offer fundamental new control over device symmetries and enable the realization of Hamiltonians unique to 2D systems.After a broad introduction, I will discuss two classes of materials and devices. First, proximitized graphene-based Josephson junctions that are gate tunable. The graphene Josephson FET enables a quantum-noise-limited parametric amplifier with performance comparable to the best discrete amplifiers in this class [1]. One can realize extremely sensitive and fast bolometers [2] – useful for dark matter search, among other applications. Second, twisted van der Waals heterostructures based on the high-temperature superconductor Bi2Sr2CaCu2O8+δ enable the realization of a high-temperature Josephson diode [3] for the first time. Such Josephson diodes offer 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-world devices.[1] "Quantum-noise-limited microwave amplification using a graphene Josephson junction" Joydip Sarkar et al. ,  Nature Nanotechnology 17, 1147 (2022).[2] “ Kerr non-linearity enhances the response of a graphene Josephson bolometer,” Sarkar et al. ,  Nature Communications volume 16, 7043 (2025).[3] "High-temperature Josephson diode," Sanat Ghosh et al. Nature Materials 23, 612 (2024).