Narrowband, angle-tuneable, helicity-dependent terahertz emission from nanowires of the topological Dirac semimetal Cd3As2

Journal article

All-optical control of terahertz pulses is essential for the development of optoelectronic devices for next-generation quantum technologies. Despite substantial research in THz generation methods, polarisation control remains difficult. Here, we demonstrate that by exploiting bandstructure topology, both helicity-dependent and helicity-independent THz emission can be generated from nanowires of the topological Dirac semimetal Cd3As2. We show that narrowband THz pulses can be generated at oblique incidence by driving the system with optical (1.55 eV) pulses with circular polarisation. Varying the incident angle also provides control of the peak emission frequency, with peak frequencies spanning 0.21 – 1.40 THz as the angle is tuned from 15° - 45°. We therefore present Cd3As2 nanowires as a promising novel material platform for controllable terahertz emission.

Authors: Boland, JL; Damry, DA; Xia, CQ; Schoenherr, P; Prabhakaran, D

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Chemical Society
• Journal: ACS Photonics
• Volume: 10
• Issue: 5
• Pages: 1473–1484
• Publication date: 2023-04-03
• Acceptance date: 2023-03-20
• DOI: 10.1021/acsphotonics.3c00068
• EISSN: 2330-4022
• Language: English
• Keywords: nanowires; terahertz; Dirac semi-metal; helicity-dependent emission; FFR; photonics