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TFDC (Thomas-Fermi-Dirac-Cheng) electron theory is applied to analyzing the characteristics of the electrons inside the double layer of the nanometer composite thin films. This paper proposes the new mechanism about the high capacity in both theoretical analysis and experimental measurement.

Higher channel capacity and noise elimination are the key requirements for the implementation of long-distance quantum communication. As the additional degrees of freedom (DoF) of photons can be employed to achieve higher channel capacity and security beyond the polarizations DoF of photons, the photonic qubits are always employed as the flying qubits in quantum communication and quantum information processing. Here, exploiting the multiple DoFs of photons, we present an efficient quantum secure direct communication protocol based on the coding and manipulation of qubits on both the polarization and the orbital angular momentum of photons. Also, the numerical simulation is studied to further clarify the improvement of the channel capacity and the security. It is found that the channel capacity and the error rate (caused by eavesdropping) of the QSDC protocol which encoded on the polarization DoF and the OAM DoF is significantly higher than that of coding on only polarization DoF. We believe this work could provide more evidence for the applications of higher-dimensional qubits in quantum information science.

According to the properties of the hyperentangled Bell state and hyper-encoding technology, this paper proposes a high-capacity quantum key distribution protocol with qudits hyper-encoded in polarization and spatial mode degrees of freedom (DOFs). In our protocol, 8 bits of information can be transmitted in one iteration. In contrast, the previous quantum key distribution protocols can only transmit up to 4 or 6 bits in one iteration. Moreover, quantum memory is unnecessary in our protocol. We analyze the relationship between the amount of eavesdropping and the success rate of eavesdropping. With the increase of eavesdropping information, the eavesdropping success probability will decrease sharply. The results show that our protocol is secure. Finally, this protocol is flexible; each qubit has two completely independent DOFs. If one DOF is destroyed, the other can still be used to transmit secure information. The protocol may be useful in the future quantum communication field.

Integrated SnO₂ electrode with hierarchical nanosheets array structure growing on three-dimensional (3D) macroporous Ni foam substrates is successfully prepared via a facile and effective template-free route. The self-supported integrated electrode can be directly used as anode for lithium-ion batteries (LIBs) without adding any ancillary materials. As a result, such integrated electrode exhibits superior electrochemical performances. It maintains a high reversible discharge capacity of 1617.8mAh$\cdot$g${}^{-1}$ and a high cycling stability of 829.2mAh$\cdot$g${}^{-1}$ even after 500 cycles. The unique structural features with large areas, shorter transport path of ion and electron as well as robust mechanical strength are probably responsible for the enhanced performance.

Hierarchical Bi₂MoO₆ nanosheet arrays (BNAs) growing on three-dimensional (3D) Ni foam are synthesized by one-step template-free route. The obtained BNAs are used as binder-free integrated electrode for Li-ion batteries (LIBs) directly. The electrode exhibits a super high reversible discharge capacity of 2311.7$\mu$Ah$\cdot$cm${}^{-2}$ (1741.4mAhg${}^{-1}$), and an excellent cycle stability. The outstanding electrochemical properties are reasonable from the self-supported integrated electrode in which the electrolyte is easy to infiltrate active materials, electrons and ions are readily transported along the 3D conductive substrate and the stable electrode structure.

VO₂(B) nanostrips were synthesized by microwave-hydrothermal method. The XRD patterns show that VO₂(B) nanostrips are pure metastable monoclinic phase. VO₂(B) nanostrips, in length of 1.5–2$\mu$m, width of 200–400nm, and thickness of 10–20nm, present exposed (001) facets and parallel alignment structure. The VO₂(B) nanostrips are composed of nanosheets with 2–5nm thickness. A very high initial discharge capacity of 318.3mAhg${}^{-1}$ is obtained and the capacity of 100th cycle is 248.5mAhg${}^{-1}$ (about 78.0% retention) at 50mAg${}^{-1}$. The capacity fades at about 4.08% per cycle for the first 10 cycles. After 10 cycles, the fading slows down to 0.32% per cycle. The rate performance shows the first discharge capacities of VO₂(B) nanostrips are 249.6, 212.0, 181.8, 161.7, and 145.2mAhg${}^{-1}$ at 0.1, 0.2, 0.4, 0.8, and 1.6Ag${}^{-1}$, respectively, with around 100% coulombic efficiency. Glycerol and microwave-hydrothermal method contribute to the shaping and thickness of VO₂(B) nanostrips with the parallel alignment nanostructure, which directly improves the electrical properties of this material.