标题： 使用红外频闪光的相位解析自旋波显微术 显示英文标题

标题： Phase-resolving spin-wave microscopy using infrared strobe light

摘要： 对敏感且可靠地探测磁化动力学的需求在各种背景下不断增加，例如在研究新型混合磁子系统时，自旋动力学与其它激发态（包括微波光子、光子或声子）强烈且相干地耦合。 量子磁子学的最新进展也突显了采用磁子相位作为量子态变量的必要性，这需要在片上微米和纳米尺度的磁子器件中高精度地检测和绘制出来。 在此，我们展示了一种简便的光学技术，该技术可以使用1550纳米波长的红外频闪光源直接执行具有空间和相位分辨率的同步光谱和成像功能。 为了展示该方法，我们对镍铁和钇铁石榴石（YIG）双层结构中的相位分辨自旋动力学进行了光谱研究，并在偶极自旋波区域对YIG的反向体积自旋波模式进行了空间成像。 使用频闪光探针，检测到的进动相位对比可以直接用来构建自旋波波前图，在自旋波传播的连续波 regime 和稳态下，而无需任何光学参考路径。 通过选择施加的磁场、频率和检测相位，自旋波图像可以对进动幅度和相位敏感。 我们的结果表明，红外光学频闪光可以作为磁光探测磁化动力学的多功能平台，可能在研究混合磁子系统方面具有重要意义。 显示英文摘要

摘要： The needs for sensitively and reliably probing magnetization dynamics have been increasing in various contexts such as studying novel hybrid magnonic systems, in which the spin dynamics strongly and coherently couple to other excitations, including microwave photons, light photons, or phonons. Recent advances in quantum magnonics also highlight the need for employing magnon phase as quantum state variables, which is to be detected and mapped out with high precision in on-chip micro- and nano-scale magnonic devices. Here, we demonstrate a facile optical technique that can directly perform concurrent spectroscopic and imaging functionalities with spatial- and phase-resolutions, using infrared strobe light operating at 1550-nm wavelength. To showcase the methodology, we spectroscopically studied the phase-resolved spin dynamics in a bilayer of Permalloy and Y3Fe5O12 (YIG), and spatially imaged the backward volume spin wave modes of YIG in the dipolar spin wave regime. Using the strobe light probe, the detected precessional phase contrast can be directly used to construct the map of the spin wave wavefront, in the continuous-wave regime of spin-wave propagation and in the stationary state, without needing any optical reference path. By selecting the applied field, frequency, and detection phase, the spin wave images can be made sensitive to the precession amplitude and phase. Our results demonstrate that infrared optical strobe light can serve as a versatile platform for magneto-optical probing of magnetization dynamics, with potential implications in investigating hybrid magnonic systems.