Yong Sheng Zhao

Circularly polarized (CP) lasers hold great potential for advancing cutting‐edge chiroptical technologies, particularly in spin information communication and high‐resolution displays, due to their unique capability to produce intense, highly coherent CP light. Most existing approaches to CP lasers still face prominent limitations, including rigorous fabrication conditions, scarce available material systems, and an inherent bottleneck in simultaneously realizing strong CP emission and efficient stimulated emission. Here, we report a simple and general host–guest strategy to construct high‐performance CP random lasing systems, where achiral MAPbX ₃ perovskite quantum dots (QDs) with different halide compositions are integrated into enantiomeric MOF via in situ encapsulation. Strong Pb−O and Eu−X coordination interactions between the chiral MOF host and achiral QD guest enable efficient chirality transfer. Meanwhile, chiral MOFs act as effective scattering centers to provide sufficient optical feedback, sustaining stable random lasing oscillation. The optimized MAPbX ₃ @P/M‐EuBTC composites exhibit stable CP random lasing with a high g _lum of 1.52. Benefiting from halide composition modulation, the system realizes broadband tunable lasing emission covering 523–747 nm. This work establishes a reliable platform for developing high‐performance CP light sources and offers valuable insights for the rational design of advanced lasing gain materials toward next‐generation CP laser devices.

Energy conversion underpins both natural processes and modern technologies, ^1,2 yet direct conversion of light into mechanical motion remains comparatively rare. ^3–7 Existing photomechanical systems generally rely on intermediate chemical or thermal energy states, limiting their ability to generate rapid, directional mechanical motion from light. We report the first electrically mediated light-to-mechanical motion conversion, realized through polar and elastic crystal motors derived from a nonpolar heptazine. Under scanning light, two polymorphs move unidirectionally at up to 1.0 µ m/s, 60-fold faster than prior photomotile crystals. Mechanistically, light irradiation generates a bulk photovoltaic effect that modulates the internal field of the crystals, inducing anisotropic inverse piezoelectric deformation. The resulting elastic energy is converted into sustained directional motion by the moving optical front, propelling the crystals antiparallel to the scanning direction. This inverse piezoelectric effect provides a direct pathway from light to mechanical motion without requiring photochemistry or photothermal effects. Beyond these classical approaches, this introduces a third photomechanical paradigm, enabling precise, fast, real-world wireless microactuation.

This review explores diverse chiral material platforms and photonic strategies for organic circularly polarized lasers, while highlighting key challenges towards their practical applications.

Highly sensitive circularly polarized light (CPL) detectors are essential for optical communication and sensing. Nevertheless, while certain CPL detectors employing single‐component and polycrystalline perovskite active layers are capable of broad‐spectrum detection range, the majority of such devices still suffer from substantial carrier recombination, leading to high energy consumption. The rational design of high‐quality p–n junctions provide a promising strategy for achieving efficient carrier separation and self‐powered operation. Here, we present a high‐performance, self‐powered CPL detector based on quasi‐two‐dimensional (quasi‐2D) chiral hybrid perovskite (CHP) p–n junction microwire (MW) arrays constructed from [(R)/(S)‐β‐MPA] ₂ (MA) _n‐1 Pb _n Br _3n+1 and [(R)/(S)‐β‐MPA] ₂ (MA) _n‐1 Pb _n Br _3n+1‐x I _x (MPA = methylphenylethylamine, MA = methylammonium). The built‐in electric field of the p–n junction, the chiral‐induced spin selectivity (CISS) effect of the CHPs, and the high crystallinity with ordered crystallographic alignment of the arrays collectively enable high‐performance self‐powered CPL detection. The device exhibits excellent CPL sensitivity across a broad spectral range of 405–556 nm, with a maximum photoresponsivity ( R _max ) of 37.7 A W ⁻¹ under 510 nm illumination, an anisotropy factor ( g _Iph ) of 0.37, and a high photocurrent on/off ratio (I _on / I _off ) of 1.29 × 10 ⁴ under 0 V bias. These superior performances highlight the device's great potential for polarization‐based optical communication and encryption applications.

Organic semiconductors are attractive for the development of flexible, wavelength‐tunable lasers. However, most reported organic micro/nanolasers rely on femtosecond‐pulsed optical pumping, which is impractical for real‐world applications. This limitation has urged the pursuit of electrically pumped organic lasers; yet their realization remains a long‐standing challenge primarily due to a fundamental materials dilemma, in which high‐gain organic semiconductors often suffer from poor, unbalanced charge transport. Here, we demonstrate that this intrinsic trade‐off can be effectively alleviated through a molecular doping strategy. Employing a high‐gain spirofluorene derivative as the emissive layer, we introduce an n‐type doped layer to construct an organic light‐emitting diode (OLED), achieving more balanced charge transport while preserving outstanding optical gain. Consequently, singlet‐polaron annihilation is significantly suppressed, as evidenced by reduced efficiency roll‐off and electrically pumped transient absorption measurements. When integrated with a distributed feedback (DFB) resonator, the resulting device exhibits ultra‐narrow (∼2 nm) electroluminescence under pulsed current injections and delivers low‐threshold nanosecond lasing under an optical–electrical co‐pumping configuration, thereby demonstrating a practical architecture for implementing organic laser diodes. Our work provides a general strategy to overcome the intrinsic paradox where high‐gain organic semiconductors struggle to maintain balanced charge transport, illuminating a pathway toward light amplification under electrical excitation.

Organic semiconductors are attractive for the development of flexible, wavelength‐tunable lasers. However, most reported organic micro/nanolasers rely on femtosecond‐pulsed optical pumping, which is impractical for real‐world applications. This limitation has urged the pursuit of electrically pumped organic lasers; yet their realization remains a long‐standing challenge primarily due to a fundamental materials dilemma, in which high‐gain organic semiconductors often suffer from poor, unbalanced charge transport. Here, we demonstrate that this intrinsic trade‐off can be effectively alleviated through a molecular doping strategy. Employing a high‐gain spirofluorene derivative as the emissive layer, we introduce an n‐type doped layer to construct an organic light‐emitting diode (OLED), achieving more balanced charge transport while preserving outstanding optical gain. Consequently, singlet‐polaron annihilation is significantly suppressed, as evidenced by reduced efficiency roll‐off and electrically pumped transient absorption measurements. When integrated with a distributed feedback (DFB) resonator, the resulting device exhibits ultra‐narrow (∼2 nm) electroluminescence under pulsed current injections and delivers low‐threshold nanosecond lasing under an optical–electrical co‐pumping configuration, thereby demonstrating a practical architecture for implementing organic laser diodes. Our work provides a general strategy to overcome the intrinsic paradox where high‐gain organic semiconductors struggle to maintain balanced charge transport, illuminating a pathway toward light amplification under electrical excitation.

Organic photonic micro/nanostructures have drawn considerable attention due to their unique advantages, such as tunable physicochemical properties and outstanding charge/photon transport characteristics, providing a powerful platform for constructing advanced nanophotonic devices. The dimension and shape of photonic building blocks have a significant impact on the photon behaviors, including the light generation, confinement, amplification, transmission, modulation and processing. The design and fabrication of multidimensional organic photonic micro/nanostructures facilitates the development of novel nanophotonic devices with desired performance. However, a comprehensive study on the synthesis strategies and photonic applications of organic micro/nanostructures with high‐level dimension morphologies is still lacking. This review summarizes the recent advances in the dimension control of organic photonic micro/nanostructures and discusses the dimension‐dependent photonic properties of organic photonic micro/nanostructures with high‐level dimension morphologies. The state‐of‐the‐art advances in diverse multidimensional photonic microdevices are overviewed, such as optical waveguides, micro/nanoscale lasers, polarization rotators, photodetectors, optical logic gates, and photonic skins. Moreover, the current challenges and outlook for the direction of future research on multidimensional organic photonic micro/nanostructures are discussed. This review aims to inspire more innovative research on the fabrication of organic photonic micro/nanostructures with high‐level dimension morphologies for next‐generation integrated optoelectronic applications.

Nanocrystal superlattices typically occur in two- or three-dimensional configurations, constrained to the micrometer scale and with limited size tunability. Here, we report one-dimensional superlattices prepared by self-assembly of CsPbBr ₃ nanorods and nanoplatelets. These exhibit a hierarchical structure, evolving from ribbons (µm) of nanorods or nanoplatelets to assemblies of ribbons (mm). These superlattices have a diameter of 0.8–1 µm and length in the range of 13–1500 µm, and their aspect ratio can be tuned from 14 to 1200 by adjusting the shape of the nanorods and nanoplatelets. Thanks to their anisotropic structure, the superlattices show strong polarized emission with a near-unity degree of polarization, ≈4 times larger than that of randomly assembled film. These superlattices also exhibit chiral optical response (circular dichroism and circularly polarized emission). Since no chiral ligands are used in the synthesis, the chiral signal (negative or positive) from the superlattices is random. However, the signal can be controlled after the addition of chiral ligands. The maximum dissymmetry factor of the luminescence ( g _lum ) is −0.11, and can be further amplified to −0.32 in the amplified spontaneous emission of the superlattices.

Circularly polarized lasers play important roles in chiroptical technologies. Organic materials have the potential for exploring multi‐color circularly polarized laser emission owing to their large diversity. However, the realization of multi‐color organic circularly polarized lasing generally requires sophisticated molecular design and time‐consuming synthesis. Here, we propose a crystal polymorphism strategy to realize multi‐color circularly polarized lasing. Three kinds of polymorphic microcrystals are synthesized from one organic compound by controlling the liquid‐phase molecular self‐assembly. The polymorphic microcrystals combine the cavity effect with multi‐color optical gain and chiroptical activity, which enable violet‐blue, blue, and cyan circularly polarized laser emission. This work establishes an organic polymorphic material platform for exploring multi‐color circularly polarized lasers.