Two-photon absorption in CMOS image sensors

This paper characterises the response of a CMOS image sensor with 2.7 μm pixels to light at 1550 nm. Two-photon absorption(TPA) occurs when two photons with an energy lower than the silicon bandgap energy interact with the same electron within ashort time window. This can be achieved by a focused pulsed laser beam above a critical light intensity. Our results show thatfor a burst of 450 fs light pulses at 1550 nm focused on a single pixel, a pulse light power of 66 mW is the minimal detectablelevel for this device. Due to the nature of TPA, the detection efficiency scales linearly with light power above this detection limit.

Jaar van publicatie:2021

Toegankelijkheid:Open