Photonics Research, 2018, 6 (3): 03000177, Published Online: Jul. 10, 2018
Improved common-path spectral interferometer for single-shot terahertz detection Download: 646次
Far infrared or terahertz Ultrafast measurements Electro-optical devices Spectroscopy, terahertz Interferometry
Abstract
To seek high signal-to-noise ratio (SNR) is critical but challenging for single-shot intense terahertz (THz) coherent detection. This paper presents an improved common-path spectral interferometer for single-shot THz detection with a single chirped pulse as the probe for THz electro-optic (EO) sampling. Here, the spectral interference occurs between the two orthogonal polarization components with a required relative time delay generated with only a birefringent plate after the EO sensor. Our experiments show that this interferometer can effectively suppress the noise usually suffered in a non-common-path interferometer. The measured single-shot SNR is up to 88.85, and the measured THz waveforms are independent of the orientation of the used ZnTe EO sensor, so it is easy to operate and the results are more reliable. These features mean that the interferometer is quite qualified for applications where strong THz pulses, usually with single-shot or low repetition rate, are indispensable.
Shuiqin Zheng, Qinggang Lin, Yi Cai, Xuanke Zeng, Ying Li, Shixiang Xu, Jingzhen Li, Dianyuan Fan. Improved common-path spectral interferometer for single-shot terahertz detection[J]. Photonics Research, 2018, 6(3): 03000177.