Advanced Optical Materials最新文献

Perovskite quantum dots (PQDs) are ideal candidates for optoelectronic devices owing to their exceptional properties. However, their practical use is hindered by instability when exposed to moisture and oxygen. Encapsulation techniques have been effective in their enhancing stability, but improving device performance remains difficult. In this study, an in-situ encapsulation technique using small organic molecules to encapsulate microwires assembled from PQDs is proposed. The encapsulation layer effectively shields the PQDs from environmental factors while maintaining excellent light-absorption properties. The fabricated photodetectors exhibit a remarkably high responsivity of 430.6 A W⁻¹ and an external quantum efficiency of 146 417%. For linearly polarized light, the devices demonstrate a dichroic ratio of up to 1.85. Even under ambient air conditions with 60% humidity for over a month, the device retains ≈60% of its original photocurrent.

Hybrid organic–inorganic perovskites with chiral organic cations are very interesting for optoelectronic applications because of their intrinsically chiral light-matter interactions. Chiral distortions in these materials lead to circular dichroism, circular birefringence, and circularly polarized luminescence in the band transitions of the inorganic sublattice. Raman-active vibrational modes in these crystals are governed by crystal symmetry and therefore are also strongly impacted by the nature and magnitude of the chiral distortions. Here, low-frequency Raman modes that are sensitive to circularly polarized excitation are reported in chiral hybrid organic–inorganic perovskites (CHOIPs) across a wide range of structures and compositions. The circularly polarized Raman spectra from enantiomers of CHOIP single crystals exhibit sharp modes below 150 cm⁻¹, corresponding to vibrations of the lead iodide octahedra. These modes exhibit strong differences in intensities (Raman optical activity, ROA) depending on the handedness of the excitation, with high degree of polarization for several modes. Calculations reveal the presence of several chiral phonon modes with opposite phonon angular momenta. The strong ROA and the chiral phonon modes are a direct consequence of chirality transfer from the chiral organic linker to the lead iodide octahedra in the CHOIP structure, resulting in a strong chiroptical response in the phonon modes.

The image illustrates the influence of group delay dispersion (GDD) on optical pulses, highlighting the chromatic dispersion and chirp that arise upon interaction with a mirror. In the Research Article (DOI: 10.1002/adom.202500727), Ulrich Galander, Oliver H. Heckl, and co-workers characterize the GDD of supermirrors designed for the mid-infrared spectral regime.

Suspended Black Phosphorus

The anisotropic suspended black phosphorus (BP) on the right exhibits an elliptical Raman mapping, while the isotropic suspended MoS₂ on the left displays a circular one. The elliptical Raman mapping has been confirmed to correlate with the crystal orientation of BP, which provides a new method for determining the crystal orientation of BP. For suspended BP-based photodetectors, the responsivity (R) reaches ≈1 A W⁻¹ at 1064 nm in the armchair direction, surpassing supported BP photodetectors by 49% in R, 89% in response time, and 45% in recovery time. More details can be found in the Research Article by Chao Wang, Jinlai Zhao, and co-workers (Doi: 10.1002/adom.202502057).

In recent years, lead halide perovskite quantum dots (PQDs) have exhibited immense potential in fabricating patterned light-emitting layers for display devices. The laser-induced in situ synthesis of PQDs is an attractive patterning method due to the advantages of high efficiency, high precision, and non-contact processing. By leveraging laser-induced photothermal, photochemical, or other effects, it triggers the crystallization of PQDs at specified locations on precursor films, thereby achieving simultaneous synthesis and patterning. This review systematically summarizes precursor system design, polymer matrix selection, and film preparation methods on in situ synthesis. And it focuses on the synthesis mechanisms under continuous-wave and pulsed laser irradiation, encompassing photothermal and other laser-induced reactions. Additionally, it demonstrates the technology's applications in high-resolution, flexible, and multi-color LED patterning. Finally, future development directions such as lead-free systems and solvent-free processes are discussed, while current challenges in environmental stability and process reproducibility are highlighted, providing insights for the scalable application of this technology.

The growing demand for advanced anticounterfeiting systems has accelerated the development of chromic materials with spatially programmable optical properties. However, optical materials exhibiting stimulus-inversed steric effects remain largely unexplored. Herein, two rationally designed luminescent Pt(II) rotors with tailored steric hindrance are presented that demonstrated unprecedented multistimulus-responsive chromic switching. In contrast to conventional steric effects where bulkier groups enhance emission, these systems display a distinct pressure-inverted behavior. The smaller-hindrance rotor 1 showed 25% pressure-enhanced phosphorescence (874 → 1092 a.u.), whereas the larger-hindrance rotor 2 underwent dramatic emission quenching of 85% (6446 → 942 a.u.). Through integration into polymer matrices, flexible smart films are fabricated capable of programmable luminescence switching, which enabled time-dependent dynamic authentication via stimulus-responsive emission signatures. The multidimensional control strategy establishes hierarchical security platforms that combine intrinsic material complexity with adaptive anticounterfeiting capabilities through sequence-dependent, multichannel decoding.

Light as a Butterfly

Forward light scattering transmits light without backward reflection. Such a property can be achieved from certain core-shell nanostructures. Here, we can imagine particle assemblies, where each particle's color is determined by its diameter. Light is scattered forward, where objects appear dark for certain observation angles, because there is zero backward reflected light. More details can be found in the Research Article by Lucien Roach, Peter Wiecha, Glenna L. Drisko, and co-workers (DOI: 10.1002/adom.202502529).

With the increasing demand for precise polarization control, metasurfaces composed of subwavelength structures emerge as a core approach due to their remarkable advantages in compactness, multifunctionality, and integrability. They show strong potential in advanced photonic applications such as optical communications, vector beam shaping, and quantum imaging. This review systematically summarizes recent progress in metasurface-based polarization manipulation across 2D real space, 3D real space, and momentum space. In 2D control, resonant phase, Pancharatnam–Berry (PB) phase and hybrid-phase design enable modulation of polarization, amplitude, and phase of scalar and vector beams, laying the groundwork for high-dimensional optical field modulation. In 3D control, both spin-decoupling and non-spin-decoupling mechanisms realize continuous evolution of longitudinal polarization states, polarization trajectory engineering, and dynamic modulation—advancing metasurface devices from planar polarization elements toward volumetric optical field modulators. Momentum-space control primarily focuses on bound states in the continuum (BICs) and quasi-BICs (qBICs), where chiral qBICs exhibit unique advantages in circular polarization and narrowband high-Q responses. This review outlines design strategies and physical mechanisms of representative metasurface-based polarization control methods, highlighting recent advances in functional integration, dimensional expansion, and reconfigurable responses.

Light–matter interactions in 2D materials gain significant interest due to their distinctive optical and electronic properties. Recently, silicates emerge as a promising new class of 2D materials, but their nonlinear optical properties remain largely unexplored. This study demonstrates the layer-dependent nonlinear absorption and optical limiting capabilities of 2D muscovite, a silicate mineral, using femtosecond laser excitation at 450 nm. The two-photon absorption (TPA) coefficient is highly sensitive to the number of layers, increasing markedly from (3.91 ± 0.06) ×10³ cm GW⁻¹ in multilayer structures to (6.94 ± 0.17) × 10⁵ cm GW⁻¹ in the monolayer limit at a peak intensity 68 GW cm⁻², highlighting a pronounced layer-dependent enhancement in nonlinear absorption. Additionally, monolayer muscovite exhibits an optical limiting threshold of 1.46 mJ cm⁻², outperforming graphene and other 2D dichalcogenides. This enhanced TPA results from quantum confinement and intrinsic lattice defects that facilitate nonlinear optical transitions. Density functional theory reveals that liquid-phase exfoliation disrupts potassium interlayers and induces oxygen vacancies, creating mid-gap electronic states that significantly enhance TPA. These insights open new avenues for designing low-fluence, high-efficiency optical limiters using 2D silicates.

Optical encryptions based on micro/nanophotonics attracts significant interest for its high security and capacity. Among promising device platforms, microcavity lasers offer distinct advantages for information labeling and encryption through unique lasing characteristics, such as spectral fingerprints. Image-like outputs, including lasing modes and patterns, facilitate parallel multimodal information processing and are compatible with integrated schemes using optoelectronic sensors and processors, although it remains largely underexplored. In this work, an imaging-based digital encryption platform is developed in principle using Fabry–Pérot (FP) microlaser arrays that are intra-cavity-integrated with custom-designed micro-optics. Microlenses (MLs) are designed and fabricated directly on a cavity mirror by two-photon lithography (TPL), forming a ML-integrated FP microcavity when paired with another mirror. By coordinating the microlens focal length with the cavity length, FP microlasers arrays are constructed with customizable high Q-factors, small mode volumes, and lasing thresholds. A spatially programmed microlens array (MLA), together with cavity length and pump energy, functions as a triple key for the optical multi-attribute encryption system. Finally, a multi-key authentication scheme based on micro Quick Response (QR) codes is demonstrated through lasing patterns of heterogeneous microlaser arrays. This work presents a digitalizable and scalable tools for all-optical or optoelectronic anti-counterfeiting and data encryption applications.