Phys.org  May 17, 2024 Quantum noise–limited homodyne detectors have applications across quantum technologies, and they comprise photonics and electronics. Researchers in the UK developed a quantum noise–limited monolithic electronic-photonic integrated homodyne detector, with a footprint of 80 micrometers by 220 micrometers, fabricated in a 250-nanometer lithography bipolar CMOS process. They measured a 15.3-gigahertz 3-decibel bandwidth with a maximum shot noise clearance of 12 decibels and shot noise clearance out to 26.5 gigahertz, when measured with a 9–decibel-milliwatt power local oscillator. This performance was enabled by monolithic electronic-photonic integration, which went below the capacitance limits of devices made up of separate […]