Graphene-integrated metamaterial device for all-electrical polarization control of terahertz quantum cascade lasers

Kindness, S. J. et al. (2019) Graphene-integrated metamaterial device for all-electrical polarization control of terahertz quantum cascade lasers. ACS Photonics, 6(6), pp. 1547-1555. (doi: 10.1021/acsphotonics.9b00411)

Abstract

Optoelectronic modulators that operate by the electrical tuning of plasmonic resonator structures have demonstrated fast (>MHz) manipulation of terahertz (THz) radiation for communications, imaging, and spectroscopy applications. Among this class of THz device, chiral metamaterial-based polarization modulators have attracted increasing attention due to the importance of THz polarization control for chemistry, biology, and spectroscopy applications, as well as for THz communication protocols. In this paper, active polarization modulation of a THz quantum cascade laser is demonstrated by the electrical tuning of a 2D chiral metamaterial array. The operating principle of this device is based on an electromagnetically induced transparency analogue, produced by the coupling between a bright resonator and two dark resonators. The orientation of these resonators is such that a radiating electric dipole orthogonal to the incident electric field polarization is induced, causing a rotation of the polarization angle of the transmitted radiation. By variably dampening the dark resonators using graphene, the coupling condition is electrically modulated such that continuous tuning of the transmitted polarization angle is achieved. This device, operating at room temperature, can be readily implemented as a fast, optoelectronic, polarization modulator with a maximum tuning range of 20 degrees at 1.75 THz, with demonstrated reconfiguration speeds of >5 MHz.

• Item Type: Articles
• Additional Information: S.J.K. acknowledges the Integrated Photonic and Electronic Systems CDT (Grant No. EP/L015455/1) for funding and support. S.J.K., N.W.A., B.W., W.M., H.E.B., D.A.R., and R.D. acknowledge financial support from the Engineering and Physical Sciences Research Council (EPSRC) (Grant No. EP/P021859/1, Hyper Terahertz). W.M. thanks the George and Lillian Schiff Foundation of the University of Cambridge for financial support and is grateful for the Honorary Vice-Chancellor’s Award of the Cambridge Trust. R.D. acknowledges support from the EPSRC (Grant No EP/S019383/1) and from the Royal Society (RSG/R1/180148 - Research Grant). S.H. and P.B.W. acknowledge funding from the EPSRC (Grant No. EP/K016636/1). P.B.W. acknowledges the EPSRC Cambridge NanoDTC (Grant No. EP/G037221/1). K.D. acknowledges financial support from the EPSRC (Grant No. EP/S019324/1, MQIC).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Delfanazari, Dr Kaveh
• Authors: Kindness, S. J., Almond, N. W., Michailow, W., Wei, B., Jakob, L. A., Delfanazari, K., Braeuninger-Weimer, P., Hofmann, S., Beere, H. E., Ritchie, D. A., and Degl’Innocenti, R.
• College/School: College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering
• Journal Name: ACS Photonics
• Publisher: American Chemical Society
• ISSN: 2330-4022
• ISSN (Online): 2330-4022
• Published Online: 22 May 2019
• Copyright Holders: Copyright © 2019 American Chemical Society
• First Published: First published in ACS Photonics 6(6):1547-1555
• Publisher Policy: Reproduced under a Creative Commons license