Non-adiabatic effects in population transfer in three-level systems

G. G. Grigoryan, Y. Pashayan-Leroy

Eugeny Korsunsky

Yang Liu, Tian‐Xiang Hou, Wenyi Liang +3 more

Hong Li, H. Z. Shen, S. L. Wu +1 more

The technique of shortcuts to adiabaticity (STA) has attracted broad attention due to their possible applications in quantum information processing and quantum control. However, most studies published so far have been only focused on Hermitian systems under the rotating-wave approximation (RWA). In this paper, we propose a modified shortcuts to adiabaticity technique to realize population transfer for a non-Hermitian system without RWA. We work out an exact expression for the control function and present examples consisting of two-and three-level systems with decay to show the theory. The results suggest that the shortcuts to adiabaticity technique presented here is robust for fast passages. We also find that the decay has small effect on the population transfer in the three-level system. To shed more light on the physics behind this result, we reduce the quantum three-level system to an effective two-level one with large detunings. The shortcuts to adiabaticity technique of effective two-level system is studied. Thereby the high-fidelity population transfer can be implemented in non-Hermitian systems by our method, and it works even without RWA.

Mustafa Demirplak

Zhao Hua, Liang Jiu Qing

The population transfer in effective three-state systems driven by laser beams has been studied based on the theory of Lewis–Riesenfeld Hermitian invariants in the full- and partial-adiabatic approximations. A strict formulation of adiabatic conditions is given and a new adiabatic condition for inducing a complete population transfer is found.