Integrated balanced homodyne detector using CMOS capacitive-feedback TIA for quantum measurements

Sarah Bastiaens; Cedric Bruynsteen; Simone Cammarata; Axl Bomhals; Leandro da Silva; Michiel Van Osta; Johan Bauwelinck; Xin Yin

arXiv · 2609.37671

Integrated balanced homodyne detector using CMOS capacitive-feedback TIA for quantum measurements

Sarah Bastiaens·Cedric Bruynsteen·Simone Cammarata·Axl Bomhals·Leandro da Silva·Michiel Van Osta·Johan Bauwelinck·Xin Yin

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Abstract

A low-noise, high-speed balanced homodyne detector is demonstrated, combining a capacitive-feedback transimpedance amplifier implemented in 28 nm CMOS with a custom photonic integrated circuit fabricated in imec's iSiPP200 silicon photonics platform. The receiver achieves a 3-dB bandwidth of 7.6 GHz, a maximum shot noise clearance of 27 dB, a shot noise-limited bandwidth of 13.7 GHz and a common-mode rejection ratio up to 54.8 dB. These results demonstrate the suitability of CMOS capacitive-feedback transimpedance amplifiers for demanding quantum and coherent sensing optical applications, including continuous-variable quantum key distribution, quantum random number generation, and optical coherence tomography.

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Sarah Bastiaens, Cedric Bruynsteen, Simone Cammarata, Axl Bomhals, Leandro da Silva, Michiel Van Osta, Johan Bauwelinck, Xin Yin. 2026-09-29. Integrated balanced homodyne detector using CMOS capacitive-feedback TIA for quantum measurements. https://arxiv.org/abs/2609.37671

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