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arXiv · 2306.07665

Liquid-Crystal-Based Controllable Attenuators Operating in the 1-4 Terahertz Band

Aniela Dunn·Zhaopeng Zhang·Michael D. Horbury·Eleanor V. Nuttall·Yingjun Han·Mohammed Salih·Lianhe Li·Abigail Bond·Ehab Saleh·Russell Harris·Diego Pardo·Brian N. Ellison·Andrew D. Burnett·Helen F. Gleeson·Alexander Valavanis
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Abstract

Liquid-crystal devices (LCDs) offer a potential route toward adaptive optical components for use in the < 2 THz band of the electromagnetic spectrum. We demonstrate LCDs using a commercially available material (E7), with unbiased birefringence values of 0.14-0.18 in the 0.3-4 THz band. We exploit the linear dichroism of the material to modulate the emission from a 3.4-THz quantum cascade laser by up to 40%, dependent upon both the liquid-crystal layer thickness and the bias voltage applied.

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Aniela Dunn, Zhaopeng Zhang, Michael D. Horbury, Eleanor V. Nuttall, Yingjun Han, Mohammed Salih, Lianhe Li, Abigail Bond, Ehab Saleh, Russell Harris, Diego Pardo, Brian N. Ellison, Andrew D. Burnett, Helen F. Gleeson, Alexander Valavanis. 2023-06-13. Liquid-Crystal-Based Controllable Attenuators Operating in the 1-4 Terahertz Band. https://arxiv.org/abs/2306.07665

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