Nanosecond pulses in a THz gyrotron oscillator operating in a mode-locked self-consistent Q-switch regime

• Published in: Physical review letters Vol. 111; no. 20; p. 205101
• Main Authors: Alberti, S, Braunmueller, F, Tran, T M, Genoud, J, Hogge, J-Ph, Tran, M Q, Ansermet, J-Ph
• Format: Journal Article
• Language: English
• Published: United States 15.11.2013
• ISSN: 1079-7114
• DOI: 10.1103/PhysRevLett.111.205101

An experimental study of a nanosecond pulsed regime in a THz gyrotron oscillator operating in a self-consistent Q-switch regime has been carried out. The gyrotron is operated in the TE(7,2) transverse mode radiating at a frequency of 260.5 GHz. The 5 W nanosecond pulses are obtained in a self-consistent Q-switch regime in which the cavity diffraction quality factor dynamically varies by nearly 2 orders of magnitude on a subnanosecond time scale via the nonlinear interaction of different mode-locked frequency-equidistant sidebands. The experimental results are in good agreement with numerical simulations performed with the TWANG code based on a slow time scale formulation of the self-consistent time-dependent nonlinear wave particle interaction equations.