Sensitivity of PBS colloidal quantum DOT photoconductors: A comparison of different readout methods

We report on colloidal PbS quantum dot near infrared photoconductors operating at low voltage. In order to maximize the device sensitivity, we exploited the advantages of different measurement techniques and methods for dark current cancellation and noise reduction including the DC volt-amperometric measurement with offset cancellation, a Wheatstone-bridge configuration and impedance measurements. We demonstrate that even photodetectors with moderate detectivity (10
⁹
-10
¹⁰
cmHz
^1/2
/W), exhibit very large SNR.