Haiyu Meng is a lecturer at the Xiangtan University, China. She received her PhD from the Hunan University in 2022. Her research interests include the physics and computational design of topological and altermagnetic photonic crystals, bound state in continuum and metasurfaces.
Yee Sin Ang is the Kwan Im Thong Hood Cho Temple Early Career Chair Professor and an Assistant Professor at the Singapore University of Technology and Design (SUTD). He was an alumnus of the 69 Lindau Nobel Laureate Meeting. He is the founding associate editor of APL Electronic Devices. He has been ranked global Top 2% scientist in Applied Physics by the Elsevier/Stanford University ranking since 2022. His research interests include the first-principles design of 2D semiconductor computing electronics, resistive switching devices, and altermagnetic spintronics.
Fig. 1.
(Color online) Altermagnetic behaviour in a photonic crystal. (a) Electronic altermagnet with opposite sublattice moments m+ and m−. (b) Fermionic band structure for tAM = 0.4; the spin-up and spin-down bands split away from the M point. Inset: spin-polarized Fermi surfaces. (c) Photonic counterpart of altermagnet: gyromagnetic elements under opposite out-of-plane bias B+ and B−, with a relative offset d. (d) Simulated photonic bands coloured by the Stokes parameter S3; the left- and right-circularly polarized branches split away from M while remaining degenerate at M. (e) Cutaway view of the fabricated crystal, comprising YIG elements, permanent magnets, metallic ground planes and access holes. (f, g) Measured momentum-resolved spectra along X-M-Y under left-circular (f) and right-circular (g) excitation; solid curves are the simulated bands. (h) Simulated isofrequency contour at 8.10 GHz, coloured by S3. (i) Corresponding measured Fourier spectra under left-circular (left) and right-circular (right) excitation; solid and dashed curves are the simulated contours for the two handednesses. The frequency of 8.10 GHz shown in (h) and (i) is representative of the 8.05–8.15 GHz window mapped in the experiment. Panels adapted with permission from Ref. [9].
DownLoad:
