Real-time near-field terahertz imaging with atomic optical fluorescence
Real-time near-field terahertz imaging with atomic optical fluorescence
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DOI：
10.1038/nphoton.2016.214
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发表时间：
2017-01-01
期刊：
影响因子：
35
通讯作者：
Weatherill, K. J.
中科院分区：
文献类型：
--
作者：
Wade, C. G.;Sibalic, N.;Weatherill, K. J.
太赫兹（THz）近场成像是一门蓬勃发展的学科（1，2），其应用范围从光束传播的基础研究（3）到超材料（4，5）和波导（6，7）的表征。超越衍射极限通常涉及光栅结构或检测器的长度尺度短于辐射波长;在太赫兹域中，这已经使用包括散射尖端（8，9）和孔径（10）在内的许多技术来实现。或者，将太赫兹场映射到光波长上并对可见光进行成像，消除了对扫描本地探头的要求，加快了图像收集时间（11，12）。在这里，我们报告太赫兹光转换使用的气体高度激发的里德伯原子。通过收集太赫兹诱导的光学荧光，我们展示了太赫兹驻波的实时图像，并使用众所周知的原子特性来校准太赫兹场强度。
Terahertz (THz) near-field imaging is a flourishing discipline(1,2), with applications from fundamental studies of beam propagation(3) to the characterization of metamaterials(4,5) and waveguides(6,7). Beating the diffraction limit typically involves rastering structures or detectors with length scale shorter than the radiation wavelength; in the THz domain this has been achieved using a number of techniques including scattering tips(8,9) and apertures(10). Alternatively, mapping THz fields onto an optical wavelength and imaging the visible light removes the requirement for scanning a local probe, speeding up image collection times(11,12). Here, we report THz-to-optical conversion using a gas of highly excited Rydberg atoms. By collecting THz-induced optical fluorescence we demonstrate a real-time image of a THz standing wave and use well-known atomic properties to calibrate the THz field strength.