Experimental demonstration of efficient pulsed terahertz emission from a stacked GaAs/AlGaAs p-i-n-i heterostructure

The pulsed optoelectronic terahertz emitter based on a d-doped p-i-n-i GaAs/Al(x)Ga(1-x)As heterostructure, which was suggested by Reklaitis [ Phys. Rev. B 77, 153309 (2008)] , is investigated experimentally. It is shown that the heterostructure can serve as efficient antenna- and bias-free surface emitter. Its power exceeds the emission from InGaAs and InAs surfaces for optical excitation fluences below 0.7 µJ/cm(2) at 82 MHz pulse repetition rate, respectively, 7 µJ/cm(2) at 1 kHz, with potential for further improvement by carrier recombination management.