A method of preparing passive materials suitable for magnetooptic interactions is shown using manganese implantation into gallium nitride (GaN) epitaxial layers, which establishes both dilute ferromagnetism and a three-level optical system with persistence to over 300 K. A sweep of thermal anneal parameters for a high implant dose into Mg-doped p-type GaN films is presented, and the materials are tested for both their magnetization and photoluminescence (PL). The optimal anneal process at 825 °C for 5 min maintains ferromagnetism with T_C>305 K, confirming magnetic alignment at room temperature with a coercivity of ~100 Oe. PL and spectrophotometry of the optimally prepared materials show the effects of the mid-gap defect state on the material’s optical characteristics. The anneal process returns the real part index to its baseline dispersion while retaining an onset of absorption starting at the defect level E_A=1.8 eV, signifying a stable mid-gap energy transition with a measured state lifetime of τ_PL=2.7 ns. The scalability of this process for producing three-level transition magnetic materials suggests passive optical or magnetooptic devices can be constructed that interconnect photonic and spintronic effects for emerging system designs and potential applications in quantum information.

IEEE Transactions on Electron Device Article Link

This work reports comprehensive modeling of photocurrent spectra generated by an InGaN/InGaN disk-in-wire photodiode based on the effective bond-orbital model. The photocurrent spectra contributed by both single-photon absorption and two-photon absorption are calculated. The physical mechanisms for the observed prominent peaks are identified and investigated.

IEEE IPC Article Link