Department of Physics, Shiraz University, Shiraz, 71454, Iran.
Department of Physics, Institute for Advanced Studies in Basic Sciences, Zanjan, 45137-66731, Iran.
Sci Rep. 2023 Jan 19;13(1):1075. doi: 10.1038/s41598-023-27949-x.
In this article, a full numerical method to study the squeezing procedure through second harmonic generation process is proposed. The method includes complex nonlinear coupling coefficient, phase mismatch, and pump depletion. Attention has been also paid to the effects of accumulated noises in this work. The final form of the numerical formula seems to be much simpler than the analytical solutions previously reported. The function of this numerical method shows that it works accurately for different mechanisms of squeezed state generations and does not suffer from instabilities usually encountered even for non-uniform, coarse steps. The proposed method is used to examine the squeezing procedure in an engineered nonlinear plasmonic waveguide. The results show that using the nonlinear plasmonic waveguide, it is possible to generate the squeezed states for the pump and the second harmonic modes with high efficiency in a propagation length as short as 2 mm which is much shorter than the needed length for the traditional nonlinear lithium niobate- based optical waveguides being of the order of 100 mm. This new method of squeezed states generation may find applications in optical communication with a noise level well below the standard quantum limit, in quantum teleportation, and in super sensitive interferometry.
本文提出了一种通过二次谐波产生过程研究压缩过程的全数值方法。该方法包括复非线性耦合系数、相位失配和泵浦损耗。本工作还关注了累积噪声的影响。数值公式的最终形式似乎比以前报道的解析解简单得多。该数值方法的功能表明，它可以准确地用于不同的压缩态产生机制，并且不会像通常遇到的那样不稳定，即使对于非均匀的、粗糙的步长也是如此。所提出的方法用于研究工程非线性等离子体波导中的压缩过程。结果表明，使用非线性等离子体波导，在 2mm 的短传播长度内就有可能以高效率产生泵浦和二次谐波模式的压缩态，这比传统的基于非线性铌酸锂的光学波导所需的长度短得多，其长度约为 100mm。这种新的压缩态产生方法可能在噪声水平远低于标准量子极限的光通信、量子隐形传态和超灵敏干涉测量中得到应用。
