Abstract-High-precision digital terahertz phase manipulation within a multichannel field perturbation coding chip

 

Hongxin Zeng, Huajie Liang, Yaxin Zhang, Lan Wang, Shixiong Liang, Sen Gong, Zheng Li, Ziqiang Yang, Xilin Zhang, Feng Lan, Zhihong Feng, Yubin Gong, Ziqiang Yang, Daniel M. Mittleman

 

Fig. 1: MFPCC architecture and its high-precision terahertz phase manipulation function.

Fig. 2: Perturbation and phase shift of a single 2DEG-PMU with 0 and 1 states.

https://www.nature.com/articles/s41566-021-00851-6

Direct phase modulation is one of the most urgent and difficult issues in the terahertz research area. Here, we propose a new method employing a two-dimensional electron gas (2DEG) perturbation microstructure unit coupled to a transmission line to realize high-precision digital terahertz phase manipulation. We induce local perturbation resonances to manipulate the phase of guided terahertz waves. By controlling the electronic transport characteristics of the 2DEG using an external voltage, the strength of the perturbation can be manipulated, which affects the phase of the guided waves. This external control permits electronic manipulation of the phase of terahertz waves with high precision, as high as 2−5° in the frequency range 0.26–0.27 THz, with an average phase error of only 0.36°, corresponding to a timing error of only 4 fs. Critically, the average insertion loss is as low as 6.14 dB at 0.265 THz, with a low amplitude fluctuation of 0.5 dB, so the device offers near-ideal phase-only modulation.