Ultraviolet/Visible Quasicylindrical Waves on Semimetal Cd₃As₂ Nanoplates

Abstract

Resolving the photonic modes in real space is essential to understand the fundamental process and control of photonic behavior in optoelectric devices. However, the understanding of the photonic modes of semimetal Cd3As2 is still lacking. Herein, the quasicylindrical waves (QCW) on Cd3As2 nanoplates using photoemission electron microscopy (PEEM) are found out. The QCW is due to the optical field scattered by subwavelength indentations, with wavelength being the same as the incident light, and their amplitude decays as r−1/2 from the edges. The transverse magnetic (TM) mode dominates the observed QCW of Cd3As2 nanoplates, which is affected by the edge structure. In broadband from UV to visible, the QCWs on Cd3As2 nanoplates are observed. Further, nanostructures to achieve subwavelength focusing and interference lattice of the Cd3As2 optical QCW are achieved. These findings demonstrate the regulation of QCW, which benefits optimizing the optoelectronic performances of semimetal materials in the future.

Recent advances in photonics of three-dimensional Dirac semimetal Cd3As2

“…It was found that QCW is of the same wavelength as the input light and decays at a rate of r1/2 from the scattering source. Transverse magnetic modes were found to dominate the QCW pattern, depending on the excitation polarization relative to the Cd3As2 nanoplate edges 164 . Additionally, numerical simulations indicated that the Cd3As2 metasurface may improve absorption when compared with naked nanoplates.…”

“… – 163 The QCW is an optical field scattered by subwavelength indentations, distributed along a surface over several wavelengths, containing both radiative and evanescent components. The optical QCW on Cd3As2 nanoplates has recently been studied 164 by a team of researchers across a wide range of wavelengths from ultraviolet (UV) to visible. It was found that QCW is of the same wavelength as the input light and decays at a rate of r1/2 from the scattering source.…”

“…16 © 2020 Wiley-VCH GmbH, (e) and (f) Ref. 164 © 2022 Wiley-VCH GmbH, and (g) Ref. 165 © 2022 Elsevier.…”

“…Transverse magnetic modes were found to dominate the QCW pattern, depending on the excitation polarization relative to the Cd 3 As 2 nanoplate edges. 164 Additionally, numerical simulations indicated that the Cd 3 As 2 metasurface may improve absorption when compared with naked nanoplates. This is advantageous with the aid of QCW, since the interference between the incoming light and QCW modes results in a stronger local field, which increases absorption.…”

High-Order Harmonic Generation in Photoexcited Three-Dimensional Dirac Semimetals

“…This frequency shift signifies the instantaneous photogeneration of free carriers in the laser field . These observations suggest that Cd 3 As 2 possesses a metal-like transient response similar to graphene, making it suitable as a high-speed device and surface plasmon–polariton (SPP) carrier . The harmonic intensity as a function of the laser power is depicted in Figure d, revealing a clear division into two distinct regions at 0.17 TW/cm 2 .…”