Superconducting Cavity-Based Sensing of Band Gaps in 2D Materials

Krishnendu Maji; Joydip Sarkar; Supriya Mandal; Sriram H.; Mahesh Hingankar; Ayshi Mukherjee; Soumyajit Samal; Anirban Bhattacharjee; Meghan P. Patankar; Kenji Watanabe; Takashi Taniguchi; Mandar M. Deshmukh

doi:10.1021/acs.nanolett.3c04990

arXiv · 2403.05867

Superconducting Cavity-Based Sensing of Band Gaps in 2D Materials

Krishnendu Maji·Joydip Sarkar·Supriya Mandal·Sriram H.·Mahesh Hingankar·Ayshi Mukherjee·Soumyajit Samal·Anirban Bhattacharjee·Meghan P. Patankar·Kenji Watanabe·Takashi Taniguchi·Mandar M. Deshmukh

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Abstract

The superconducting coplanar waveguide (SCPW) cavity plays an essential role in various areas like superconducting qubits, parametric amplifiers, radiation detectors, and studying magnon-photon and photon-phonon coupling. Despite its wide-ranging applications, the use of SCPW cavities to study various van der Waals 2D materials is relatively unexplored. The resonant modes of the SCPW cavity exquisitely sense the dielectric environment. In this work, we measure the charge compressibility of bilayer graphene coupled to a half-wavelength SCPW cavity. Our approach provides a means to detect subtle changes in the capacitance of the bilayer graphene heterostructure, which depends on the compressibility of bilayer graphene, manifesting as shifts in the resonant frequency of the cavity. This method holds promise for exploring a wide class of van der Waals 2D materials, including transition metal dichalcogenides (TMDs) and their moir\'e where DC transport measurement is challenging.

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Krishnendu Maji, Joydip Sarkar, Supriya Mandal, Sriram H., Mahesh Hingankar, Ayshi Mukherjee, Soumyajit Samal, Anirban Bhattacharjee, Meghan P. Patankar, Kenji Watanabe, Takashi Taniguchi, Mandar M. Deshmukh. 2024-03-09. Superconducting Cavity-Based Sensing of Band Gaps in 2D Materials. https://doi.org/10.1021/acs.nanolett.3c04990

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