Generation linewidth of mode-hopping spin torque oscillators

Iacocca, Ezio, Heinonen, Olle, Muduli, P. K. and Åkerman, Johan (2014) Generation linewidth of mode-hopping spin torque oscillators. Physical Review B, 89 (5). 054402. ISSN 1098-0121

Preview

Text Generation_linewidth_of_mode_hopping_spin_torque_oscillators.pdf - Accepted Version Download (750kB) | Preview

Abstract

Experiments on spin torque oscillators commonly observe multimode signals. Recent theoretical works have ascribed the multimode signal generation to coupling between energy-separated spin wave modes. Here, we analyze in detail the dynamics generated by such mode coupling. We show analytically that the mode-hopping dynamics broaden the generation linewidth and makes it generally well described by a Voigt line shape. Furthermore, we show that the mode-hopping contribution to the linewidth can dominate, in which case it provides a direct measure of the mode-hopping rate. Due to the thermal drive of mode-hopping events, the mode-hopping rate also provides information on the energy barrier separating modes and temperature-dependent linewidth broadening. Our results are in good agreement with experiments, revealing the physical mechanism behind the linewidth broadening in multimode spin torque oscillators.

Actions (login required)

View Item

Downloads