9:30 AM - 11:30 AM
▲ [20a-PB3-2] Enhanced terahertz emission of gallium arsenide thin film with integrated porous silicon distributed Bragg reflector
Keywords:Bragg Reflectors, Optical properties of photonic structures
The THz emission of a 550nm-thick MBE-grown undoped/n-type gallium arsenide (GaAs) thin film with integrated porous silicon distributed Bragg reflector (PSi DBR) is presented. The active GaAs film has a total thickness less than the penetration depth of the 800nm excitation source, while the PSi DBR substrate was designed as a reflecting substrate for the transmitted photons at the film-substrate interface. A 67% increase in the peak-to-peak THz signal was observed when the emitter was compared to a similar GaAs film on bulk silicon (Si) substrate. The achieved improvement was accounted to the increased light absorption in the active layer.