Single-photon detection enabled by negative differential conductivity in moir\'e superlattices

Krystian Nowakowski; Hitesh Agarwal; Sergey Slizovskiy; Robin Smeyers; Xueqiao Wang; Zhiren Zheng; Julien Barrier; David Barcons Ruiz; Geng Li; Riccardo Bertini; Matteo Ceccanti; Iacopo Torre; Bert Jorissen; Antoine Reserbat-Plantey; Kenji Watanabe; Takashi Taniguchi; Lucian Covaci; Milorad V. Milošević; Vladimir Fal'ko; Pablo Jarillo-Herrero; Roshan Krishna Kumar; Frank H. L. Koppens

arXiv · 2505.13637

Single-photon detection enabled by negative differential conductivity in moir\'e superlattices

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Abstract

Detecting individual light quanta is essential for quantum information, space exploration, advanced machine vision, and fundamental science. Here, we introduce a novel single photon detection mechanism using highly photosensitive non-equilibrium electron phases in moir\'e materials. Using tunable bands in bilayer graphene/hexagonal-boron nitride superlattices, we engineer negative differential conductance and a sensitive bistable state capable of detecting single photons. Operating in this regime, we demonstrate single-photon counting at mid-infrared (11.3 microns) and visible wavelengths (675 nanometres) and temperatures up to 25 K. This detector offers new prospects for broadband, high-temperature quantum technologies with CMOS compatibility and seamless integration into photonic integrated circuits (PICs). Our analysis suggests the mechanism underlying our device operation originates from negative differential velocity, and represents an important milestone in the field of high-bias transport in two-dimensional moir\'e quantum materials.

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Krystian Nowakowski, Hitesh Agarwal, Sergey Slizovskiy, Robin Smeyers, Xueqiao Wang, Zhiren Zheng, Julien Barrier, David Barcons Ruiz, Geng Li, Riccardo Bertini, Matteo Ceccanti, Iacopo Torre, Bert Jorissen, Antoine Reserbat-Plantey, Kenji Watanabe, Takashi Taniguchi, Lucian Covaci, Milorad V. Milošević, Vladimir Fal'ko, Pablo Jarillo-Herrero, Roshan Krishna Kumar, Frank H. L. Koppens. 2025-05-19. Single-photon detection enabled by negative differential conductivity in moir\'e superlattices. https://arxiv.org/abs/2505.13637

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