负介电各向异性液晶中光孤子和反常调制不稳定性的观测
Observation of Optical Solitons and Abnormal Modulation Instability in Liquid Crystals with Negative Dielectric Anisotropy
摘要：
本文从理论和实验上研究了在外加电压作用下，具有负介电各向异性的垂直排列在$80μm$厚度平面盒中的液晶中光束的传输。预测了液晶的非局域非线性经历一个负非线性折射率系数的振荡响应函数。我们发现，振荡的非局域非线性可以支持稳定的亮孤子，这在实验中观察到。在一定的空间频率下，当增益系数为无穷大时，会出现反常的调制不稳定性，而不依赖于光束强度。在很低的光强（$0.26W/cm^2$）下观察到液晶的调制不稳定性，当光束功率变化2-3个数量级时，最大增益频率保持不变。
英文摘要：
We investigate theoretically and experimentally the optical beam propagation in the nematic liquid crystal with negative dielectric anisotropy, which is aligned homeotropically in a $80μm$-thickness planar cell in the presence of an externally voltage. It is predicted that the nonlocal nonlinearity of liquid crystal undergo an oscillatory response function with a negative nonlinear refractive index coefficient. We found that the oscillatory nonlocal nonlinearity can support stable bright solitons, which are observed in experiment. We also found that abnormal modulation instability occurs with infinity gain coefficient at a fixed spatial frequency, which is no depend on the beam intensity. We observed the modulation instability in the liquid crystal at a very low intensity ($0.26W/cm^2$), and the maximum gain frequency were found kept unchange when beam power changes over 2-3 orders of magnitude.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
