Abstract-Terahertz generation with ballistic photodiodes under pulsed operation

Stefan Malzer, Christian Müller-Landau, Heiko B Weber, Gottfried H Döhler, Stephan Winner,  Peter G Burke, Arthur Gossard,  Sascha Preu

http://iopscience.iop.org/article/10.1088/1361-6641/aae5e4

We investigate high field and ballistic carrier transport in a 1.55 μm photomixing
 device based on pin-diodes by time resolved terahertz (THz) spectroscopy. The device
 consists of 3 stacked In(Al)GaAs pin diodes (n-i-pn-i-p superlattice) attached to a
 broadband logarithmic-periodic antenna. Each pin diode is optimized for exhibiting
 ballistic transport and a reduced transit time roll-off. Ballistic transport signatures
 could be confirmed directly in these experiments. The data are compared with results
 from continuous-wave (CW) experiments and from simulations both supporting our
 theoretical expectations. It is demonstrated that n-i-pn-i-p superlattice photomixers
 are also efficient THz emitters under pulsed operation, showing a maximum THz field
 strength of ~0.5 V/cm (peak to peak) at 30 mW average optical power.