Observation of backward high-harmonic emission from solids.
Observation of backward high-harmonic emission from solids.
复制标题
固体后向高次谐波发射的观测。
DOI：
10.1364/oe.26.012210
复制
发表时间：
2018
期刊：
影响因子：
3.8
通讯作者：
David A. Reis
中科院分区：
文献类型：
--
作者：
G. Vampa;Y. You;Hanzhe Liu;S. Ghimire;David A. Reis
实验证明了MgO和Si晶体在镜面反射方向上反向发射近红外激光的高次谐波。我们证明了高次谐波功率随入射角的变化可以用最初为微扰非线性导出的非线性反射系数来预测。透射和反射几何形状的比较表明，反向传播的高谐波是研究强光在固体中的非线性传播的一个很好的参考。向后发射将使高谐波光束的相位匹配和扩展气相高谐波光束线的功能集成到单个光学元件中。实现相位匹配的潜力为基于固态的高谐波源铺平了道路，这种源比基于传输的最佳源具有更高的通量，在传输源中，高谐波被晶体本身强烈吸收。
We experimentally demonstrate backward emission of high-harmonics of a near-infrared laser from MgO and Si crystals in the direction of specular reflection. We show that the variation of the high-harmonic power with the angle of incidence can be predicted with nonlinear reflection coefficients derived originally for perturbative nonlinearities. A comparison of transmission and reflection geometries suggests that backward-propagating high-harmonics are an excellent reference to study nonlinear propagation of intense light in solids. Backward emission will enable phase matching of the high-harmonic beam and the integration of the functionalities of extended gas-phase high-harmonic beamlines into a single optical element. The potential to achieve phase matching paves the way to solid-state based high-harmonic sources with higher flux than the best transmission-based sources, where high-harmonics are strongly absorbed by the crystal itself.