Studies of photocurrent and dark current in quantum dots-in-a-well infrared photodetectors
(English)Manuscript (preprint) (Other academic)
The performance of quantum dots-in-a-well infrared photodetectors (DWELL IPs) has been studied by means of interband and intersubband photocurrent measurements as well as dark current measurements. Using interband photocurrent measurements, substantial escape of electrons from lower lying states in the DWELL structure at large biases was revealed. Furthermore, a significant variation of the escape probability from energy states in the DVELL sturcture with voltage was observed. These facts could be possible explanations to the strong temperature and voltage dependence of hoth photocurrent and dark current in DWELL IPs. In a comparison between DWELL IPs and quantum well infrared photocdetectors (QWIPs), the dark current was shown to be considerably lower in DWELL IPs than in QWIPs, but alos the responsivity was low in comparison to QWIPs.
IdentifiersURN: urn:nbn:se:liu:diva-53588OAI: oai:DiVA.org:liu-53588DiVA: diva2:289848