Prof. Mandar M. Deshmukh (TIFR) - Graphene Josephson junction-based parametric amplifiers and sensors

2D van der Waals materials-based heterostructures have led to new fundamental science and applications devices. Superconducting graphene-based Josephson devices offer unique opportunities to engineer new functionality for quantum technology. I will discuss two experiments - first, proximitized graphene-based Josephson junctions lead to a quantum noise-limited parametric amplifier with performance comparable to the best discrete amplifiers in this class [1]. Gate tunability of the center frequency of the amplifier, rather than flux, offers key advantages. In the second work, we extend graphene JPA architecture to make state-of-the-art bolometers leveraging graphene's low specific heat and harnessing its non-linear response.

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

[2] “Kerr non-linearity enhances the response of a graphene Josephson bolometer," Sarkar et al. arXiv:2502.04911