论文标题
基于不变工程的总和频率产生的完整和强大的能量转换
Complete and robust energy conversion by sum frequency generation based on Invariant Engineering
论文作者
论文摘要
我们提出了一种分析方法，以基于Lewis-Riesenfeld不变理论来实现总和频率产生的完整能量转换。该技术比量子力学中的两级原子过渡得出，比常规方法更有效，更健壮。在我们的方案中，建立了准绝热的单个控制参数模型，并选择了单个控制参数的值，以使初始特征态完美地转换为我们需要的最终特征态。对应于非线性频率转换过程，非线性晶体结构是通过最佳控制理论的逆工程设计设计的，这对于耦合系数和相位不匹配的扰动是可靠的，包括泵强度和晶体极化周期变化，并在任何晶体长度上导致了几乎100％的转换效率。证明频率转化率可以在2.6μm-3.6μm的波长范围内实现，当晶体长度L = 1 mm时，转化效率的光谱带宽在50％以上接近400 nm。
We propose an analytical method to achieve complete energy conversion in sum frequency generation based on Lewis-Riesenfeld invariants theory. This technique, derived from a two-level atom transition in quantum mechanics, is more efficient and robust than conventional methods. In our scheme, the quasi-adiabatic single control parameter model is established, and the value of single control parameter is selected to make the initial eigenstate perfectly converted to the final eigenstate we need. Corresponds to the nonlinear frequency conversion process, the nonlinear crystal structure is designed with the inverse engineering of optimal control theory, which is robust against the perturbations in the coupling coefficient and phase mismatch, including pump intensity and crystal polarization period variations, and results in almost 100% conversion efficiency at any crystal length. It is demonstrated that the frequency conversion can be achieved in the wavelength range of 2.6 μm -3.6 μm with a spectral bandwidth of the conversion efficiency over 50% approaching to 400 nm when the crystal length L=1 mm.
