Single‐Layered Reflective Metasurface Achieving Simultaneous Spin‐Selective Perfect Absorption and Efficient Wavefront Manipulation

Abstract

As the 2D counterpart of metamaterials, metasurfaces have drawn wide attentions in recent years due to their unique electromagnetic (EM) properties and subwavelength footprints. Although great efforts have been made in metasurface‐based full vectorial manipulation of EM waves, the realization of multifunctional devices with high compactness is still challenging. Here, by employing the mutual coupling between the meta‐atoms to induce spin‐selective magnetic resonance, a generalized design principle based on single‐layered metasurface is proposed that can achieve giant chiral absorption with average circular dichroism larger than 80%. In addition, arbitrary wavefront manipulation for reflected waves can also be realized with operation efficiency larger than 88%. As a proof of concept, three kinds of chiral devices including beam deflector, vortex beam generator, and meta‐hologram are numerically investigated in infrared region with high performance. It is believed that these multifunctional devices with simple geometry have great potentials in the field of chiral imaging, chiroptical spectroscopy, and EM communication.

Reconfigurable Continuous Meta-Grating for Broadband Polarization Conversion and Perfect Absorption

“…As such, a quasi-continuous device was designed with a chessboard-like configuration, consisting of orthogonally arranged meta-gratings [ 44 ]. When the GST is in A-state, according to the theory of geometric phase (also known as Pancharatnam–Berry phase) [ 45 ], the proposed meta-grating can be treated as a highly efficient phase retarder, since the cross-polarized amplitude is much larger than its co-polarized counterpart. In this case, the reflected phase for a crossed polarized wave is twice the orientation angle of the meta-grating.…”

Multistate Nonvolatile Metamirrors with Tunable Optical Chirality

“…Among them, metamirrors for chiral absorption (also known as chiral mirrors) that reflect one circularly polarized light (CPL) while absorbing the other with the opposite handedness are of great importance in the fields of chiral spectroscopy and imaging since chirality is an intrinsic feature that has been widely found in DNA, proteins, crystals, and some species. Until now, chiral mirrors already enabled many applications such as spin-selective light detectors, 20 polarization-dependent anomalous reflection, 21 and chiral second-harmonic generation. 22 The general method to achieve chiral mirrors was investigated by using symmetry considerations in terms of intrinsic or extrinsic chirality.…”

Deterministic preparation of W states via spin-photon interactions

“…Similarly, instead of quantum dots, spin states in solid-state materials such as silicon-vacancy centers in diamond [41,42] and silicon carbide [43,44] can be considered as alternative platforms. Besides, various novel phenomena such as spin selective metasurfaces [45], chiral molecules [46], chiral metamirrors [47], and chiral coupling of valley excitons [48] can be utilized to perform the operations required in the present scheme. Achieving high coherence times even in the room temperature, NV centers coupled to high quality optical cavities enable significant advances in quantum information science.…”