Efficient Terahertz Room-Temperature Photonic Crystal Laser

Summary form only given. Photonic crystals (PCs) allow unprecedented control over radiative properties of embedded emitters. High-Q cavities defined in PCs confine photons to small volume, enabling strong light-matter interaction. Lasers in particular stand to gain considerably through decreased lasing threshold, modulation rate, cost, form factor, and device integration. We discuss a THz-modulation photonic crystal laser in a GaAs membrane. The device draws on a multiple quantum well (MQW) gain medium that was surface-passivated using a (NH₄)S treatment to reduce nonradiative recombination losses. The increased efficiency alleviates heating problems and allows room temperature operation in pulsed mode, showing extremely fast pulses with FWHM detector in the THz regime and ultra-low-threshold (< 5muW) continuous-wave (CW) lasing at low temperature.