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Spintronics and molecular chemistry have achieved remarkable achievements separately. Their combination can apply the superiority of molecular diversity to intervene or manipulate the spin-related properties. It inevitably brings in a new type of functional devices with a molecular interface, which has become an emerging field in information storage and processing. Normally, spin polarization has to be realized by magnetic materials as manipulated by magnetic fields. Recently, chiral-induced spin selectivity (CISS) was discovered surprisingly that non-magnetic chiral molecules can generate spin polarization through their structural chirality. Here, the recent progress of integrating the strengths of molecular chemistry and spintronics is reviewed by introducing the experimental results, theoretical models, and device performances of the CISS effect. Compared to normal ferromagnetic metals, CISS originating from a chiral structure has great advantages of high spin polarization, excellent interface, simple preparation process, and low cost. It has the potential to obtain high efficiency of spin injection into metals and semiconductors, getting rid of magnetic fields and ferromagnetic electrodes. The physical mechanisms, unique advantages, and device performances of CISS are sequentially clarified, revealing important issues to current scientific research and industrial applications. This mini-review points out a key technology of information storage for future spintronic devices without magnetic components.

Organic phosphorescence, originating from triplet excitons, has potential for the development of new generation of organic optoelectronic materials. Herein, two heavy‐atom‐free room‐temperature phosphorescent (RTP) electron acceptors with inherent long lifetime triplet exctions are first reported. These two 3D‐fully conjugated rigid perylene imide (PDI) multimers, as the best nonfullerene wide‐bandgap electron acceptors, exhibit a significantly elevated T1 of ≈2.1 eV with a room‐temperature phosphorescent emission (τ = 66 µs) and a minimized singlet–triplet splitting as low as ≈0.13 eV. The huge spatial congestion between adjacent PDI skeleton endows them with significantly modified electronic characteristics of S1 and T1. This feature, plus with the fully‐conjugated rigid molecular configuration, balances the intersystem crossing rate and fluorescence/phosphorescence rates, and therefore, elevating E T1 to ≈2.1 from 1.2 eV for PDI monomer. Meanwhile, the highly delocalized feature enables the triplet charge‐transfer excitons at donor–acceptor interface effectively dissociate into free charges, endowing the RTP electron acceptor based organic solar cells (OSCs) with a high internal quantum efficiency of 84% and excellent charge collection capability of 94%. This study introduces an alternative strategy for designing PDI derivatives with high‐triplet state‐energy and provides revelatory insights into the fundamental electronic characteristics, photophysical mechanism, and photo‐to‐current generation pathway., The long‐lived excitons are of significance to alleviate the strong morphology‐ and thickness‐dependence of organic photovoltaic performance and therefore accelerating its industrialization process. Here, two room‐temperature phosphorescent electron acceptors with long‐lived triplet exctions and high‐energy level are investigated systematically for the first time. This work provides revelatory insights into their fundamental electronic characteristics, photophysical mechanism, and photo‐to‐current generation pathway.

A 3D surface-enhanced Raman scattering (SERS) sensor is realized on the facet of an optical fiber. A SERS radar configuration consisting of a parabolic mirror and a 3D spherical SERS body is designed. The parabolic mirror is used to focus the excitation laser light onto the surface of the SERS body, and to collect and reflect the Raman scattered light back into the optical fiber. The SERS body's surface consists of microscale trenches and is covered with gold nanogratings and nanoparticles on a thick gold film with a thin SiO2 spacer. Nanoscale 3D printing technology, thermal evaporation, and UV laser pulse irradiation are used to fabricate and metalize the mold of the 3D SERS radar configuration. The performance of this Au-based SERS fiber sensor is competitive with those of Ag-based SERS fiber sensors reported in the literature. It exhibits a detection limit of 10−6m for crystal violet in ethanol using 30 mW of 785 nm excitation (off resonance with the crystal violet electronic absorption) and 10 s acquisition time. Such a 3D scheme expands the design possibilities of SERS nanostructures on the facets of optical fibers enormously.

A thin-film photonic lens is fabricated using chirped plasmonic grating structures, which enables off-axis focusing and simultaneous de-multiplexing of the incident light beams, as well as the intrinsic function of an optical lens for imaging. This planar two-dimensional photonic device may be used either as a positive (converging) or a negative (diverging) lens through controlling how the light beam is incident and how the device is oriented, which defines multifold ‘diode’ effects and is thus termed “forward” or “backward” biasing of such a ‘diode’ lens. This plasmonic photonic diode (PPD) features by unidirectional functions instead of non-reciprocal transmission. These unique functions are demonstrated by focusing different colors into different angles and different focal lengths with large dispersions, which enables direct wavelength division de-multiplexing with high resolution and high efficiency. Strong plasmonic scattering by the gold nanolines that constitute the chirped grating structures leads to efficient operation and polarization-dependent performance of the PPD device.

Nanoscale photonic structures are patterned directly by exposing a thin film of conjugated polymer to the interference pattern of UV laser beams, thus inducing crosslinking between the polymer molecules in the bright fringes. The crosslinked polymer molecules become indissolvable in organic solvent due to the localized photochemical modification, enabling successful lift-off of the soft grating structures. The resultant nanodevice exhibits excellent chemical and physical stability. This demonstrates the high spatial resolution of the crosslinking process and introduces a direct nanofabrication technique, which may be utilized in the design of optoelectronic and laser devices.