High THz Average Power Generation From Photoconductive Connected Array Antenna Excited by High-Power Laser

Abstract

We report on high power THz emission from LT-GaAs photoconductive emitters, excited with a frequency-doubled, high power ultrafast Yb laser emitting 100 fs pulses at 515 nm (green) at a high repetition rate of 91 MHz. The device presented in this work incorporates a dedicated connected array. First, we describe the general methodology for designing impedance matched photoconductive connected array devices, then we describe how this methodology was applied for the design of a 361-element photoconductive connected array specifically optimized for the high optical power (20 W) at 515 nm laser wavelength and 91 MHz repetition rate. The combination of these optimized devices and a high power laser at very high repetition rate allow us to demonstrate a high THz power of 10.1 mW during the on-cycle of a chopper with 50% duty cycle.