[17p-K305-1~12] 3.13 Silicon photonics, Photonics-electronics convergence, Optical control

1:30 PM - 1:45 PM JST(4:30 AM - 4:45 AM UTC)

[17p-K305-1] [The 57th Young Scientist Presentation Award Speech] Voltage-output optical power monitor using InGaAs/Si hybrid phototransistor and on-chip Si resistor

〇Tomohiro Akazawa¹, Qiang Li², Lo Guo-Qiang², Kasidit Toprasertpong¹, Shinichi Takagi¹, Mitsuru Takenaka¹ (1.The Univ. of Tokyo, 2.Advanced Micro Foundry)

Keywords:

optical device,photodetector,photonic integrated circuit

Si programmable optical circuits (PICs) are attracting attention for promising applications such as computing applications, however, accurate programming of PICs requires calibration of the phase error of many integrated optical phase shifters. The calibration can be achieved simply through the direct monitoring of the optical power at each optical switch in the circuit. In conventional photodetection systems, photocurrent is electrically amplified by a transimpedance amplifier (TIA) and converted to voltage. On the other hand, a simpler method has been proposed in which photocurrent is directly converted to voltage by a high-resistance load. In this research, we report on a simple method to monitor weak optical signals as voltage signals without using a TIA by integrating a highly-sensitive InGaAs/Si hybrid phototransistor, with CMOS-compatible on-chip Si resistors, enabling small-footprint and low-power photodetection.