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تسجيل مستخدم جديدPerformance of superadiabatic stimulated Raman adiabatic passage in the presence of dissipation and Ornstein-Uhlenbeck dephasing
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In this paper we evaluate the performance of two superadiabatic stimulated Raman adiabatic passage (STIRAP) protocols derived from Gaussian and sin-cos pulses, under dissipation and Ornstein-Uhlenbeck noise in the energy levels. We find that for small amplitudes of Stokes and pump pulses, the population transfer is mainly achieved directly through the counterdiabatic pulse, while for large amplitudes the conventional STIRAP path dominates. This kind of hedging leads to a remarkable robustness against dissipation in the lossy intermediate state. For small pulse amplitudes and increasing noise correlation time the performance is decreased, since the dominant counterdiabatic pulse is affected more, while for large pulse amplitudes, where the STIRAP path dominates, the efficiency is degraded more for intermediate correlation times (compared to the pulse duration). For the Gaussian superadiabatic STIRAP protocol we also investigate the effect of delay between pump and Stokes pulses and find that under the presence of noise the performance is improved for increasing delay. We conclude that the Gaussian protocol with suitably chosen delay and the sin-cos protocol perform quite well even under severe noise conditions. The present work is expected to have a broad spectrum of applications, since STIRAP has a crucial role in modern quantum technology.
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