Ye Ming Qing

Controlling and manipulating temperature at the nanoscale hold substantial promise for advancing applications such as photothermal therapy, nanoscale chemical reactions, and micro/nanodevices.

Opaque metagratings remove specular power through material dissipation and nonzero reflected diffraction, but zero‐order spectra cannot distinguish these destinations once higher orders propagate. Oblique metallization turns a reciprocal opaque metagrating into a direction‐selective power router. Cross‐sectional scanning electron microscopy identifies two one‐sided Ag/SiO ₂ morphologies. Simplified models derived from these cross sections reproduce the principal measured transverse‐magnetic zero‐order angular–spectral features using unmodified standard optical functions. Opposite incidence is tested by rotating each specimen in plane by . Order‐resolved calculations reveal that reciprocity‐enforced equality of can hide strongly different power partitions. At 606 nm and , reversing the incidence changes from 0.005 to 0.724 and from 0.936 to 0.217. Lateral mirroring reverses the routing sign, mirror‐symmetric controls suppress it, and closure of the nonzero reflected order at the Rayleigh boundary eliminates it. The framework also reproduces the zero‐order response of an Al/TiO ₂ system. Relative higher‐order measurements on an additional specimen support direction‐dependent diffraction. More broadly, this morphology‐defined, Rayleigh‐gated routing shifts opaque‐metagrating design from suppressing of specular reflection to selecting radiative or dissipative power flow, with potential for integrated beam redirection and photothermal conversion.

Programmable metasurfaces have opened what is believed to be new avenues for dynamic wavefront control, yet achieving high-resolution, independent, and real-time phase control for dual-circular polarizations remains a significant challenge. In this paper, a dual-circularly polarized 2-bit programmable metasurface is proposed, characterized by a simple structure, dynamic beam scanning, and multiple polarization modes. The meta-element adopts an opposite-chirality-coexisted structure and integrates merely two varactors. By adjusting the bias voltage applied to the varactors, the meta-element achieves independent and continuous phase tuning over approximately 270° for orthogonal circular polarizations, which provides sufficient coverage for 2-bit phase programmability and enables versatile wavefront manipulation. For verification, a metasurface prototype is fabricated and experimentally characterized. Both simulation and measurement results demonstrate that the metasurface can achieve dynamic beam scanning within a range of ± 40° for multiple polarization modes. With its low-cost architecture, dynamic beam control, and flexible polarization agility, the proposed metasurface represents a promising candidate for applications in next-generation satellite communications, polarization-diverse radar detection, and remote sensing platforms.

The metasurface reaches a calculated nonreciprocity of 0.92 at 1° incidence and supports multiple tunable spectral branches. Separating directional asymmetry from spectral tuning provides a modular route to reconfigurable thermal emission.

We study here lateral asymmetric transmission (AT), a phenomenon in which the transmission under illumination from the same half‐space depends on the sign of the in‐plane wavevector, versus . Such lateral AT can emerge in reciprocal systems without polarization conversion when broken lateral mirror symmetry is combined with multiport diffraction. We experimentally and numerically investigate this effect in directionally Ag‐coated nanogratings, whose one‐sided metal coating breaks the lateral mirror symmetry. Rigorous coupled‐wave analysis shows that channel opening establishes the multiport scattering basis, whereas structure‐dependent resonant responses modulate the redistribution of power among transmission, reflection, and absorption channels. Field and normalized local‐loss distributions corroborate stronger metallic dissipation under excitation and greater transmission under excitation. Angle‐resolved measurements and morphology‐informed simulations show the same sign and principal angular–spectral evolution of the lateral transmission contrast. The design principle is further examined in directionally Al‐coated PMMA– gratings on a substrate. These results identify broken lateral mirror symmetry as the structural prerequisite and higher‐order diffraction‐channel opening as the multiport basis for reciprocal lateral AT, with structure‐dependent resonant coupling modulating the attainable contrast.

Breaking Lorentz reciprocity in thermal radiation typically requires extreme grazing angles, suffering from severe geometric projection losses and state volatility. Here, we propose a dynamic, non‐volatile, nonreciprocal absorber integrating a phase‐change (GST) grating atop a magneto‐optical InAs waveguide. Leveraging the transverse magneto‐optical response in the Voigt configuration and precise momentum matching, the metagrating achieves strong nonreciprocal absorption contrast () at a near‐normal incidence angle of under a moderate magnetic field. The device enables continuous spectral steering via incident angle and magnetic field, alongside non‐volatile digital latching of the nonreciprocal state via GST switching. Through non‐Hermitian perturbation theory, we unveil that nonreciprocity quenching during the phase transition originates synergistically from spatial field redistribution and loss‐induced damping. Our findings provide a robust, non‐volatile platform for advanced thermal emission control.

We propose a dual-band near-infrared absorber based on the simultaneous excitation of borophene localized surface plasmons (LSPs) and Tamm plasmon polaritons (TPPs). By leveraging the ultrahigh intrinsic carrier density of borophene, this hybrid architecture effectively overcomes the mid-infrared spectral limitations of conventional two-dimensional materials, achieving near-perfect peak absorptances of 98.1% and 97.2%. Theoretical and numerical investigations reveal that the in-plane LSP mode and the longitudinally distributed TPP mode exhibit a highly decoupled nature. The LSP resonance can be actively and independently modulated via the borophene ribbon geometry and electron density, whereas the TPP mode is strictly governed by the underlying one-dimensional photonic crystal and incident angle. Combined with a robust polarization-selective response, this structurally simple yet highly tunable platform offers a versatile physical paradigm for designing next-generation active optical modulators and polarization-sensitive nanophotonic devices.

We propose and theoretically investigate a thermally tunable, dual-channel near-infrared absorber based on an amorphous silicon (a-Si)-integrated hybrid grating-photonic crystal. Utilizing rigorous coupled-wave analysis and coupled-mode theory, we demonstrate that the device achieves polarization-selective, near-perfect absorption (>98%) governed by mode-selective critical coupling. Due to distinct spatial confinement, the structure exhibits a completely decoupled thermal response. One resonant mode achieves critical coupling with a high linear thermal sensitivity of 118.3 pm/°C, while the other acts as an ultra-high- Q reference ( Q ≈13147) that remains spectrally locked with a negligible sensitivity of 4.4 pm/°C. Furthermore, the absorber features high fabrication tolerance and angular mode anti-crossing. This integration of an actively tunable channel and a temperature-insensitive reference within a single monolithic platform provides a robust paradigm for self-calibrating optical sensors and dynamic narrowband filters.

Nonreciprocal radiation is essential for advanced thermal photonics but is constrained by static performance and large incident angle requirements in current Weyl semimetal (WSM)-based devices. Here, we propose a WSM–Ge2Sb2Te5 (GST) hybrid resonant structure to achieve thermally tunable dual functionality. When GST is amorphous, the structure exhibits strong small-angle (5°) nonreciprocal radiation at 14.09 μm, with a nonreciprocity coefficient of up to 0.95, driven by coupled guided-mode and Fabry–Pérot resonances. Upon annealing, GST transforms to the crystalline state, enabling broadband high absorption across 12–15 μm with reciprocal behavior. Structural parameters modulate the resonant wavelength by adjusting the effective refractive index or optical path, while GST crystallinity significantly regulates nonreciprocal performance. This non-volatile design overcomes key limitations of static nonreciprocal devices, holding promise for adaptive energy harvesting and intelligent electromagnetic protection.