Shrekenhamer David, Watts Claire M, Padilla Willie J
Department of Physics, Boston College, 140 Commonwealth Ave, Chestnut Hill, MA 02467, USA.
Opt Express. 2013 May 20;21(10):12507-18. doi: 10.1364/OE.21.012507.
We present a single pixel terahertz (THz) imaging technique using optical photoexcitation of semiconductors to dynamically and spatially control the electromagnetic properties of a semiconductor mask to collectively form a THz spatial light modulator (SLM). By co-propagating a THz and collimated optical laser beam through a high-resistivity silicon wafer, we are able to modify the THz transmission in real-time. By further encoding a spatial pattern on the optical beam with a digital micro-mirror device (DMD), we may write masks for THz radiation. We use masks of varying complexities ranging from 63 to 1023 pixels and are able to acquire images at speeds up to 1/2 Hz. Our results demonstrate the viability of obtaining real-time and high-fidelity THz images using an optically controlled SLM with a single pixel detector.
我们展示了一种单像素太赫兹（THz）成像技术，该技术利用半导体的光激发来动态和空间地控制半导体掩模的电磁特性，从而共同形成一个太赫兹空间光调制器（SLM）。通过使太赫兹光束和准直的光学激光束共同穿过高电阻率硅晶片，我们能够实时修改太赫兹传输。通过使用数字微镜器件（DMD）在光束上进一步编码空间图案，我们可以为太赫兹辐射编写掩模。我们使用从63到1023像素不等的不同复杂度的掩模，并能够以高达1/2 Hz的速度获取图像。我们的结果证明了使用具有单像素探测器的光控SLM获得实时和高保真太赫兹图像的可行性。
