Injection Locking of Resonant Tunneling Diode Oscillator with a Single-Frequency Terahertz Wave

A resonant tunneling diode oscillator has been successfully injection-locked to a continuous terahertz wave. The locking range is about 50 MHz when the RTD emission power and the injection power are set to 10 μW and 4 μW, respectively. The dependence of the locking range to the injection power is consistent with the Adler's theory.