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An efficient implementation scheme for the BFV fully homomorphic encryption algorithm was proposed on the Zynq platform. This scheme effectively integrated the negative wrapped convolution with the number theoretic transform (NTT) algorithm, optimizing and accelerating the polynomial multiplication process. Furthermore, it adopted a pipeline design and parallel hardware architecture to enhance the RNS implementation of the BFV algorithm. The system efficiently implemented data transmission between the ARM processor and FPGA using the AXI-DMA transfer mechanism. Test results on the Zynq UltraScale+MPSoC ZCU102 platform show that the system performs a homomorphic addition in just 0.024 ms and a homomorphic multiplication in 5.779 ms at a 200 MHz clock frequency, which includes 0.874 ms for ciphertext transmission. Compared to the implementations of the SEAL and OpenFHE libraries, the proposed scheme achieves efficiency improvements of 4.63 and 6.79 times for homomorphic addition, and 4.43 and 2.95 times for homomorphic multiplication, providing an important reference for the practical engineering implementation of fully homomorphic encryption algorithms.

Aiming at the problems such as lack of specific algorithms for process implementation, using public keys in most of the solutions, low efficiency in dealing with large-scale data sets, and lack of applicability, a unilateral shuffling protocol was proposed, and on this basis, a shuffling protocol based on additive secret sharing was designed. The share conversion algorithm was constructed through the casual transfer protocol, and the shuffling was completed without exposing the original data set. The shuffling task was decomposed into multiple sub-tasks by the Benes arrangement network, which improved the efficiency of large-scale data sets. Finally, through the additive secret sharing, the shuffling shares were safely distributed to the participants. The correctness of the proposed shuffling protocol was analyzed strictly, and its security property was evaluated by using an ideal-reality simulation paradigm. Compared with the existing literature, the proposed protocol can meet the current security standards in security, and has high efficiency in processing large-scale data sets. It improves the applicability of the protocol and further promotes its application in the current environment.

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.

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.

This paper proposes a novel Switching Chaotic Coupled Map Lattices (SCCML) system based on Elementary Cellular Automata (ECA) to address issues found in Coupled Map Lattices (CML) systems such as period windows, poor lattice correlation, and limited chaotic behavior parameters. The system uses a bidirectional coupling method and introduces two ECA with different rules to continuously alter the indexes of the coupled lattices and the underlying chaotic mapping. This approach effectively mitigates correlation issues in CML systems. At the same time, the iterative results of ECA are cascaded with the chaotic mapping as a perturbation of the SCCML system to extend the parameter range of chaotic behavior. The Kolmogorov–Sinai entropy density and universality, bifurcation diagrams, uniformity and correlation are analyzed to investigate the dynamical properties of the proposed system. Theoretical analysis and numerical simulations demonstrate that, compared with other novel spatiotemporal chaotic systems, the proposed system eliminates periodic windows, expands the chaotic behavior parameter range, and decreases the correlation between different lattices. The above experimental results demonstrate the proposed system's excellent potential for cryptosystems and secure communication. Furthermore, an Encrypted Code Index Modulation (E-CIM) scheme based on reversible ECA encryption is proposed to address the problems of limited pseudo-random sequence resources and low spectrum utilization in direct sequence spread spectrum systems. The proposed scheme uses a chaotic sequence with good correlation and randomness generated by the SCCML spatiotemporal chaos system as the spreading code sequence. In the scheme, the information bits are divided into two parts, namely modulation bits and mapping bits. The modulation bits are mapped to points on the modulation constellation diagram. The mapping bits are encrypted using reversible ECA, and the mapped bits before and after encryption are mapped as spreading sequences with different indexes. Simulation and analysis show that under the same spectrum efficiency conditions, the BER performance of E-CIM is superior to that of the Code Index Modulation (CIM) and Generalized Code Index Modulation (GCIM) schemes by about 2–4 dB and superior to that of the Nonorthogonal Code Shift Keying and Code Index Modulation (N-CSK-CIM) scheme by about 0.5 dB in an additive Gaussian white noise channel when the BER is 10 − 5 . [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]

Plasmonic waveguides, as a competitive candidate, have been widely studied in rapid developing photonic integrated circuits (PICs) and optical interconnection fields. However, crosstalk between plasmonic waveguides is a critical issue that has to be considered in practice. Actually, crosstalk dominates the ultimate integration density of the planar photonic circuits. This paper reviews the recent research work on evaluation methods and crosstalk suppression approaches of plasmonic waveguides. Three crosstalk evaluation methods based on comparison of specific parameters of waveguides have been summarized. Furthermore, four specific approaches to reduce crosstalk have been illustrated as two categories according to their impacts on waveguide performances and the whole circuit. One means of crosstalk suppression is changing the placement of waveguides, which could maintain the transmission characteristics of the original waveguide. The other means is inserting medium, which has the advantage of occupying smaller space compared to the first method. Consequently, to suppress crosstalk between plasmonic waveguides, one should choose suitable approach.

Transmission characteristic differences of a narrow bandpass filter between p- and s-polarized light, especially the central wavelength separation, will corrupt the performance of the filter when the incidence is oblique. In this paper, by adding high-index materials asymmetrically to both sides of a low-index spacer, which tunes the equivalent index of the spacer, the central wavelengths of the two polarizations coincide perfectly when in 20[degrees] incidence; with different reflected layers on the two sides of the spacers and replacing some reflected layers with equivalent layers, the 0.5 dB normalized passband width is kept at 0.2 nm, which meets the requirement of the 50 G dense wavelength division multiplexer filter. OCIS codes: 310.0310, 310.6860, 060.4510, 230.7408.