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Register a new userRabi oscillations in two-level systems beyond the rotating-wave approximation
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Adriano de Albuquerque Batista
Publication date
2015
fields
Physics
and research's language is
English
Authors
Adriano A. Batista
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Here we use perturbation techniques based on the averaging method to investigate Rabi oscillations in cw and pulse-driven two-level systems (TLSs). By going beyond the rotating-wave approximation, especifically to second-order in perturbation, we obtain the Bloch-Siegert shift of the TLS resonant frequency, in which the resonant frequency increases with the driving field amplitude. This frequency shift implies that short resonant $pi$-pulses in which the Rabi frequency is approximately 40% or higher of the transition frequency do not achieve complete inversion in TLSs. Hence, guided by analytical results based on the averaging technique, we propose two methods for obtaining population
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