Saha Soham, Diroll Benjamin T, Ozlu Mustafa Goksu, Chowdhury Sarah N, Peana Samuel, Kudyshev Zhaxylyk, Schaller Richard D, Jacob Zubin, Shalaev Vladimir M, Kildishev Alexander V, Boltasseva Alexandra
School of Electrical and Computer Engineering, Birck Nanotechnology Center, Purdue University, West Lafayette, IN, USA.
Argonne National Laboratory, Lemont, IL, 60439, USA.
Nat Commun. 2023 Sep 21;14(1):5877. doi: 10.1038/s41467-023-41377-5.
All-optical switches control the amplitude, phase, and polarization of light using optical control pulses. They can operate at ultrafast timescales - essential for technology-driven applications like optical computing, and fundamental studies like time-reflection. Conventional all-optical switches have a fixed switching time, but this work demonstrates that the response-time can be controlled by selectively controlling the light-matter-interaction in so-called fast and slow materials. The bi-material switch has a nanosecond response when the probe interacts strongly with titanium nitride near its epsilon-near-zero (ENZ) wavelength. The response-time speeds up over two orders of magnitude with increasing probe-wavelength, as light's interaction with the faster Aluminum-doped zinc oxide (AZO) increases, eventually reaching the picosecond-scale near AZO's ENZ-regime. This scheme provides several additional degrees of freedom for switching time control, such as probe-polarization and incident angle, and the pump-wavelength. This approach could lead to new functionalities within key applications in multiband transmission, optical computing, and nonlinear optics.
全光开关利用光控脉冲来控制光的幅度、相位和偏振。它们可以在超快的时间尺度上运行，这对于诸如光学计算等技术驱动的应用以及诸如时间反射等基础研究至关重要。传统的全光开关具有固定的开关时间，但这项工作表明，通过在所谓的快材料和慢材料中选择性地控制光与物质的相互作用，可以控制响应时间。当探针在其近零介电常数（ENZ）波长附近与氮化钛强烈相互作用时，双材料开关具有纳秒级响应。随着探针波长的增加，响应时间加快了两个数量级以上，因为光与更快的掺铝氧化锌（AZO）的相互作用增加，最终在AZO的ENZ区域附近达到皮秒级。该方案为开关时间控制提供了几个额外的自由度，如探针偏振、入射角和泵浦波长。这种方法可能会在多波段传输、光学计算和非线性光学等关键应用中带来新的功能。
