Anomalous light-to-electricity conversion of low dimensional semiconductor in p-n junction and interband transition quantum well infrared detector

Recently, high localized carrier extraction efficiency and enhanced absorption coefficient were observed in low-dimensional semiconductor within a p-n junction. In this work, we report the discovery and verification of the phenomenon, and the performance of the first photon detector based on the interband transition of strained InGaAs/GaAs quantum wells (QWs). By introducing the resonant excitation photoluminescence, the same phenomena are observed in several different material systems. More than 95% of the photoexcited carriers escape from InGaN/GaN QWs, and 87.3% in InGaAs/GaAs QWs and 88% in InAs/GaAs quantum dots are observed. The external quantum efficiency of the device is measured to be 31% by using an absorption layer with only 100 nm effective thickness in the case without an anti-reflection layer. Using such a high value of quantum efficiency, an absorption coefficient of 3.7104 cm-1 is calculated, which is obviously larger than previously reported values. The results here demonstrate the possibility of fabricating high-performance and low-cost infrared photon detectors.