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arXiv · 2512.11497

Response times of two-dimensional photodetectors limited by intrinsic resistance and capacitance

Ilya Safonov·Dmitry Svintsov
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Abstract

Most contemporary architectures of photodetectors based on two-dimensional materials include global gates for carrier density control and local p-n junctions in the channel. We study the dependence of photocurrent in such detectors on the light modulation frequency, fully taking into account the effects of distributed resistance and gate-channel capacitance. The decay of photocurrent with modulation frequency governs the response time. We find that the maximum modulation frequency is largely determined by the position of light-sensitive junction with respect to the middle of the channel. Largest modulation frequency is achieved for junctions in immediate vicinity of either source or drain contacts, while fast roll-off of the modulation characteristic is observed for junction in the middle of the channel.

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Ilya Safonov, Dmitry Svintsov. 2025-12-12. Response times of two-dimensional photodetectors limited by intrinsic resistance and capacitance. https://arxiv.org/abs/2512.11497

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