Photoconductive arrays on insulating substrates for high-field terahertz generation.
Photoconductive arrays on insulating substrates for high-field terahertz generation.
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DOI：
10.1364/oe.391656
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发表时间：
2020-05
期刊：
影响因子：
3.8
通讯作者：
D. R. Bacon;T. Gill;M. Rosamond;A. Burnett;Aniela Dunn;Lianhe H. Li;E. Linfield;A. Davies;P. Dean;J. Freeman
中科院分区：
文献类型：
--
作者：
D. R. Bacon;T. Gill;M. Rosamond;A. Burnett;Aniela Dunn;Lianhe H. Li;E. Linfield;A. Davies;P. Dean;J. Freeman
我们报道了大面积光导太赫兹阵列结构的设计、制备和表征，该阵列结构由薄薄的LT-GaAs有源区通过晶片尺度键合工艺转移到绝缘衬底上组成。电绝缘的透明衬底减少了器件中的寄生电流，允许在带宽>；5太赫兹上产生高达120千伏厘米-1的峰值太赫兹电场。这些结果是使用比传统光导阵列和其他产生高场太赫兹辐射的流行方法所要求的更低的脉冲能量来实现的。对两种尺寸的器件进行了充分的表征，并将其发射特性与通过光整流产生的ZnTe进行了比较。该装置可以在光学饱和状态下工作，以抑制激光噪声。
We report on the design, fabrication and characterisation of large-area photoconductive THz array structures, consisting of a thin LT-GaAs active region transferred to an insulating substrate using a wafer-scale bonding process. The electrically insulating, transparent substrate reduces the parasitic currents in the devices, allowing peak THz-fields as high as 120 kV cm-1 to be generated over a bandwidth >5 THz. These results are achieved using lower pulse energies than demanded by conventional photoconductive arrays and other popular methods of generating high-field THz radiation. Two device sizes are fully characterised and the emission properties are compared to generation by optical rectification in ZnTe. The device can be operated in an optically saturated regime in order to suppress laser noise.