期刊
MATERIALS TODAY
卷 43, 期 -, 页码 27-36出版社
ELSEVIER SCI LTD
DOI: 10.1016/j.mattod.2020.10.023
关键词
-
资金
- U.S. Department of Energy, Office of Science [DE-AC02-06CH11357]
- Air Force Office of Scientific Research [FA9550-18-1-0002, FA9550-19-S-0003]
- U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering [DE-SC0017717]
- Office of Naval Research Grant [N00014-20-1-2199]
- DARPA/DSO Extreme Optics and Imaging (EXTREME) program [HR00111720032]
Modulation of dielectric permittivity enables control over the phase, amplitude, and polarization of light, crucial for tunable optical devices. This study reports significant permittivity changes induced by optically generated free carriers in zinc oxide thin films, with up to 70% broadband reflectance modulation in metal-backed mirrors.
The dielectric permittivity of a material encapsulates the essential physics of light-matter interaction into the material's local response to optical excitation. Photo-induced modulation of the permittivity can enable an unprecedented level of control over the phase, amplitude, and polarization of light. Therefore, the detailed dynamic characterization of technology-relevant materials with substantially tunable optical properties and fast response times is a crucial step to realize tunable optical devices. This work reports on the extraordinarily large permittivity changes in zinc oxide thin films (up to similar to 3.6 relative change in the real part of the dielectric permittivity at 1600 nm wavelength) induced by optically generated free carriers. We demonstrate broadband reflectance modulation up to 70% in metal-backed oxide mirrors at the telecommunication wavelengths, with picosecond-scale relaxation times. The epsilon near zero points of the films can be dynamically shifted from 8.5 mm to 1.6 mm by controlling the pump fluence. The modulation can be selectively enhanced at specific wavelengths employing metal-backed zinc oxide disks while maintaining picosecond-scale switching times. This work provides insights into the free-carrier assisted permittivity modulation in zinc oxide and could enable the realization of novel dynamic devices for beam-steering, polarizers, and spatial light modulators.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据