We propose an optically pumped nonpolar GaN/AlGaN quantum well(QW) active region design for terahertz(THz) lasing in the wavelength range of 30 μm~ 40 μm and operating at room temperature.The fast longitudinal ...We propose an optically pumped nonpolar GaN/AlGaN quantum well(QW) active region design for terahertz(THz) lasing in the wavelength range of 30 μm~ 40 μm and operating at room temperature.The fast longitudinal optical(LO) phonon scattering in GaN/AlGaN QWs is used to depopulate the lower laser state,and more importantly,the large LO phonon energy is utilized to reduce the thermal population of the lasing states at high temperatures.The influences of temperature and pump intensity on gain and electron densities are investigated.Based on our simulations,we predict that with a sufficiently high pump intensity,a room temperature operated THz laser using a nonpolar GaN/AlGaN structure is realizable.展开更多
基金Project supported in part by the National Major Basic Research Program of China (Grant No. 2011CB925603)the Shanghai Municipal Major Basic Research Project (Grant No. 09DJ1400102)
文摘We propose an optically pumped nonpolar GaN/AlGaN quantum well(QW) active region design for terahertz(THz) lasing in the wavelength range of 30 μm~ 40 μm and operating at room temperature.The fast longitudinal optical(LO) phonon scattering in GaN/AlGaN QWs is used to depopulate the lower laser state,and more importantly,the large LO phonon energy is utilized to reduce the thermal population of the lasing states at high temperatures.The influences of temperature and pump intensity on gain and electron densities are investigated.Based on our simulations,we predict that with a sufficiently high pump intensity,a room temperature operated THz laser using a nonpolar GaN/AlGaN structure is realizable.