Spectral Tuning In Quantum Rings By Magnetic Field: Detection From NIR To FIR Regime

Abstract In this work, we present a quantum ring structure based on semiconducting QWs for spectral tuning in a wide IR range (1.24- 103 µm) using an external magnetic field. We have used a tight binding method to investigate the optical properties of the structure. Using this method the effect of the external magnetic field on the absorption spectrum has been investigated as the post-processing method. Also, the effect of different geometrical parameters like the number of QWs, QR radius, and constructed material considered as processing methods for tuning absorption. The results show for GaAs based QR with the radius of 100/π consist of 4 QWs, absorption peak linearly increase from 100 meV (12.4 um) in LWIR regime and shift to 200 meV (6.2 um) in MIR regime with increasing external magnetic field. Also for a QR with a radius of 200/π, by changing the magnetic field different absorption peaks appear and disappear in an absorption spectrum and a multi-color detector converts to single-detector in the NIR regime. This results help experimentalist to select proper materials with optimized geometrical parameters to achieve desired wavelength for various detection applications.