Scaling limit in high multiplicity photo-EMF adaptive photoreceivers

Summary form only given.Photo-induced EMF provides an attractive means to perform adaptive interferometry that is insensitive to speckle or vibrations. One particular application is for laser-based ultrasound detection if the sensitivity of the technique can be improved. The responsivity of conventional photo-EMF receivers has suffered from small photoconductive gain, which have prevented their widespread use. We showed previously that the photo-EMF signal can be enhanced, at constant intensity, by using asymmetric interdigitated contacts to collect the EMF current. In the present work we studied the scaling of this enhancement up to 128 pairs of collecting contacts.