Optically Pumped Lasing at 353 nm Using Non-polar a-plane AlGaN Multiple Quantum Wells over r-plane Sapphire

摘要

We report an optically-pumped alternative nitride-based laser with room-temperature emission at 353 nm. The active region comprised of non-polar a-plane Al_(0.04)Ga_(0.96)N/Al_(0.08)Ga_(0.92)N multiple quantum wells whereas the lasing cavity consisted of Al_(0.15)Ga_(0.85)N clad and Al_(0.10)Ga_(0.85)N waveguide layers and naturally cleaved facet mirrors. The layers were grown over r-plane sapphire substrates by metalorganic chemical vapor deposition technique. A room temperature lasing threshold lor N_2-laser photoexcitation of 110kW/cm~2 and a modal optical gain of 215 cm~(-1) was measured at the peak emission wavelength.