Improved figure of merit for noise in avalanche photodiodes

We propose a new noise figure for avalanche photodiodes (APDs). This new noise figure overcomesthe difficulty of estimating the internal multiplication and quantum efficiency in complex APD structures, such as III-V SAM APDs. Measurements of the new noise figure are presented for two commercial SAM APDs and we show theoretically that it represents a more complete figure of merit for comparing the performance of one APD with another, and with the ideal.