An ultra efficient, internally regulated signal amplification mechanism for light detection in semiconductors

Avalanche photodiodes based on impact ionization can amplify optical signals, but the gain is associated with large excess noise and requires high bias near or above breakdown (for Geiger mode). Here we present a detector using the cycling excitation process (CEP) for signal amplification. This can be realized in a heavily compensated Si p-n junction, and shows ultra high gain at very low bias (<4 V), possess an intrinsic, phonon-mediated regulation process to keep the device stable without any quenching device required in today's Geiger-mode avalanche detectors.