搜索

x
中国物理学会期刊

基于SU(3)李代数在无旋转波近似下三能级系统的非绝热布居数转移

CSTR: 32037.14.aps.74.20241504

Non-adiabtic population transfer in SU(3) Lie algebra based three-level system without the rotating wave approximation

CSTR: 32037.14.aps.74.20241504
PDF
HTML
导出引用
  • 外场驱动的三能级量子系统能够利用受激拉曼非绝热通道实现量子态相干布居数转移. 本文在无旋转波近似下, 利用SU(3)李代数方法逆向设计了可严格求解的三能级系统, 研究了系统的动力学行为. 结果表明, 通过设定控制参数相应的边界条件, 无论是在理想演化下, 还是在考虑脉冲截断和中间态衰变的实际演化中, 都可以实现高保真度的布居数转移. 与现有的其他非绝热量子调控方案相比, 本方案在非绝热动力学过程中不会产生Rabi振荡和脉冲的奇异性.

     

    Coherent population transfer in quantum systems is of fundamental importance in many fields such as atomic and molecular collision dynamics, and information processing for qubit systems. Stimulated Raman nonadiabatic passage technique, when implemented in an externally driven three-level system, provides an efficient approach for realizing accelerated population transfer while maintaining robust quantum coherence, with no need of rotating wave approximation. However, previous protocols employ multiple pulses and imply that Rabi frequencies have a few oscillations during dynamical evolution. In this work, under the condition of two-photon resonance, we use a gauge transformation method to inversely design a Λ-configuration three-level system that can be solved exactly. By using SU(3) transformation, we establish the relationship between Schrödinger representation and gauge representation, where the effective Hamiltonian is an Abelian operator. Subsequently, we construct the desired Hamiltonian and further investigate its dynamic behavior. The result shows that by imposing appropriate boundary conditions on the control parameters, high-fidelity population transfer can be achieved in ideal evolution. In addition, for the practical case with pulse truncation and intermediate state decay, the fidelities of specific models can reach about 99.996% and 99.983%, respectively. Compared with other existing nonadiabatic quantum control schemes, the present scheme has the distinctive advantages. We achieve the required quantum control by applying only a few sets of Stokes and pump pulses without introducing any additional microwave field. This method does not exhibit Rabi oscillations in the dynamic process, nor does it produce singularities in the pulse itself.

     

    目录

    /

    返回文章
    返回