The noise characteristics of MgZnO/ZnO quantum cascade detectors

Abstract

The noise characteristics of MgZnO/ZnO quantum cascade detectors (QCDs) under dark stationary conditions are investigated by the dark noise model, which includes all the possible bound-to-bound intersubband transitions. The band structure is numerically calculated considering the built-in electric field induced by polarization. Results show that the noise dark current density, derived by the Nyquist theorem, increases with increasing temperature, but the noise curves are gradually stabilized with increasing voltage. Furthermore, the diagonal transitions related to E2 and E3 dominate the noise dark current density, and the noise can be improved by optimizing the structure of the MgZnO/ZnO QCD.