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Gallium phosphide (GaP) has been increasingly prioritized, fueled by the enormous demands in visible light applications such as biomedical and quantum technologies. GaP has garnered tremendous attention in nanophotonics thanks to its high refractive index, indirect bandgap width of 2.26 eV, lattice perfectly matched with silicon, and omnipotent and competitive nonlinear optical properties. Herein, we review the progress and application of GaP in nanoscale devices over the past two decades. The material properties of bulk GaP are first listed, followed by a summary of the methodologies for fabricating nanoscale devices and related integration techniques. Then, we digest the operational mechanisms across different GaP-based devices on their optical linear responses. Following this, we categorize the GaP nonlinear optical effects into multiple aspects including second-harmonic generation, four-wave mixing, Kerr optical frequency combs, etc. Ultimately, we present a perspective on GaP nanophotonics in the context of coexisting and competing modes of various nonlinear effects. We believe that a comprehensive overview of unique GaP will propel these nanophotonic devices toward a mature state, underpinning foundational understanding and leveraging practical innovations.

In order to solve the inadequacy of traditional blind signature schemes in resisting quantum computing attacks during interactions between users, signers, and verifiers was addressed, a novel quantum-resistant blind signature scheme named CDBS was proposed. This scheme aimed to enhance security and could resist quantum computing attacks. The scheme was based on the post-quantum digital signature algorithm CRYSTALS-Dilithium, selected by national institute of standards and technology (NIST). The overall scheme adopted the Fiat-Shamir signature structure, which comprised five stages, such as key generation, blinding, signing, unblinding and verification. The scheme incorporated rejection sampling technology to prevent key leakage and used NTT algorithm to optimise polynomial computation, thereby enhancing the efficiency of both signature generation and verification. Security analysis indicated that the scheme satisfied correctness, blindness, and unforgeability based upon module learning with error (MLWE) and small integer solution (SIS) problems. The scheme showed higher security and more efficient signature generation processes with smaller overhead than other lattice-based blind signature schemes. Given the same parameters, the overall computing overhead in the scheme was only 67.1% of the MBS scheme. Through software testing, an average time was only 657.65 μs to complete one blind signature and verification process. This work provided a valuable reference for the extended application on the CRYSTALS-Dilithium digital signature algorithm. [ABSTRACT FROM AUTHOR]

Extending the ionic conductivity is the pre‐requisite of electrolytes in fuel cell technology for high‐electrochemical performance. In this regard, the introduction of semiconductor‐oxide materials and the approach of heterostructure formation by modulating energy bands to enhance ionic conduction acting as an electrolyte in fuel cell‐device. Semiconductor (n‐type; SnO2) plays a key role by introducing into p‐type SrFe0.2Ti0.8O3‐δ (SFT) semiconductor perovskite materials to construct p‐n heterojunction for high ionic conductivity. Therefore, two different composites of SFT and SnO2 are constructed by gluing p‐ and n‐type SFT‐SnO2, where the optimal composition of SFT‐SnO2 (6:4) heterostructure electrolyte‐based fuel cell achieved excellent ionic conductivity 0.24 S cm−1 with power‐output of 1004 mW cm−2 and high OCV 1.12 V at a low operational temperature of 500 °C. The high power‐output and significant ionic conductivity with durable operation of 54 h are accredited to SFT‐SnO2 heterojunction formation including interfacial conduction assisted by a built‐in electric field in fuel cell device. Moreover, the fuel conversion efficiency and considerable Faradaic efficiency reveal the compatibility of SFT‐SnO2 heterostructure electrolyte and ruled‐out short‐circuiting issue. Further, the first principle calculation provides sufficient information on structure optimization and energy‐band structure modulation of SFT‐SnO2. This strategy will provide new insight into semiconductor‐based fuel cell technology to design novel electrolytes. [ABSTRACT FROM AUTHOR]