“…Moreover, the noise equivalent power (NEP, W Hz −1/2 ) and the specific detectivity (
, cm Hz 1/2 W −1 or Jones) represent the ability of PDs to detect weak light signals. The NEP is given by
, [
2 ] where J n is the dark current noise spectral density, which mainly originates from the dark current density ( J dark ). [
50 ] Thus, the specific detectivity
can be derived from the NEP as
.…”