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1.
Ruo-Ting Yang 《中国物理 B》2022,31(9):98501-098501
Rapid single flux quantum (RSFQ) circuits are a kind of superconducting digital circuits, having properties of a natural gate-level pipelining synchronous sequential circuit, which demonstrates high energy efficiency and high throughput advantage. We find that the high-throughput and high-speed performance of RSFQ circuits can take the advantage of a hardware implementation of the encryption algorithm, whereas these are rarely applied to this field. Among the available encryption algorithms, the advanced encryption standard (AES) algorithm is an advanced encryption standard algorithm. It is currently the most widely used symmetric cryptography algorithm. In this work, we aim to demonstrate the SubByte operation of an AES-128 algorithm using RSFQ circuits based on the SIMIT Nb03 process. We design an AES S-bbox circuit in the RSFQ logic, and compare its operational frequency, power dissipation, and throughput with those of the CMOS-based circuit post-simulated in the same structure. The complete RSFQ S-bbox circuit costs a total of 42237 Josephson junctions with nearly 130 Gbps throughput under the maximum simulated frequency of 16.28 GHz. Our analysis shows that the frequency and throughput of the RSFQ-based S-bbox are about four times higher than those of the CMOS-based S-bbox. Further, we design and fabricate a few typical modules of the S-box. Subsequent measurements demonstrate the correct functioning of the modules in both low and high frequencies up to 28.8 GHz.  相似文献   
2.
Yandong Guo 《中国物理 B》2022,31(12):127201-127201
Controlling the spin transport at the single-molecule level, especially without the use of ferromagnetic contacts, becomes a focus of research in spintronics. Inspired by the progress on atomic-level molecular synthesis, through first-principles calculations, we investigate the spin-dependent electronic transport of graphene nanoflakes with side-bonded functional groups, contacted by atomic carbon chain electrodes. It is found that, by rotating the functional group, the spin polarization of the transmission at the Fermi level could be switched between completely polarized and unpolarized states. Moreover, the transition between spin-up and spin-down polarized states can also be achieved, operating as a dual-spin filter. Further analysis shows that, it is the spin-dependent shift of density of states, caused by the rotation, that triggers the shift of transmission peaks, and then results in the variation of spin polarization. Such a feature is found to be robust to the length of the nanoflake and the electrode material, showing great application potential. Those findings may throw light on the development of spintronic devices.  相似文献   
3.
Xinwen Ma 《中国物理 B》2022,31(9):93401-093401
The research progresses on the investigations of atomic structure and collision dynamics with highly charged ions based on the heavy ion storage rings and electron ion beam traps in recent 20 years are reviewed. The structure part covers test of quantum electrodynamics and electron correlation in strong Coulomb field studied through dielectronic recombination spectroscopy and VUV/x-ray spectroscopy. The collision dynamics part includes charge exchange dynamics in ion-atom collisions mainly in Bohr velocity region, ion-induced fragmentation mechanisms of molecules, hydrogen-bound and van de Waals bound clusters, interference, and phase information observed in ion-atom/molecule collisions. With this achievements, two aspects of theoretical studies related to low energy and relativistic energy collisions are presented. The applications of data relevant to key atomic processes like dielectronic recombination and charge exchanges involving highly charged ions are discussed. At the end of this review, some future prospects of research related to highly charged ions are proposed.  相似文献   
4.
Wenjun Yan 《中国物理 B》2022,31(11):110704-110704
Li dendrites and electrolyte leakage are common causes of Li-ion battery failure. H2, generated by Li dendrites, and electrolyte vapors have been regarded as gas markers of the early safety warning of Li-ion batteries. SnO2-based gas sensors, widely used for a variety of applications, are promising for the early safety detection of Li-ion batteries, which are necessary and urgently required for the development of Li-ion battery systems. However, the traditional SnO2 sensor, with a single signal, cannot demonstrate intelligent multi-gas recognition. Here, a single dual-mode (direct and alternating current modes) SnO2 sensor demonstrates clear discrimination of electrolyte vapors and H2, released in different states of Li-ion batteries, together with principal component analysis (PCA) analysis. This work provides insight into the intelligent technology of single gas sensors.  相似文献   
5.
The development of phononic crystals, especially their interaction with topological insulators, allows exploration of the anomalous properties of acoustic/elastic waves for various applications. However, rapidly and inversely exploring the geometry of specific targets remains a major challenge. In this work, we show how machine learning can address this challenge by studying phononic crystal beams using two different inverse design schemes. We first develop the theory of phononic beams using the transfer matrix method. Then, we use the reinforcement learning algorithm to effectively and inversely design the structural parameters to maximize the bandgap width. Furthermore, we employ the tandem-architecture neural network to solve the training-difficulty problem caused by inconsistent data and complete the task of inverse structure design with the targeted topological properties. The two inverse-design schemes have different adaptabilities, and both are characterized by high efficiency and stability. This work provides deep insights into the combination of machine learning, topological property,and phononic crystals and offers a reliable platform for rapidly and inversely designing complex material and structure properties.  相似文献   
6.
Life on Earth uses a common set of L-amino acids (L-aa) to construct proteins and D-nucleosides (D-Nu) to form nucleic acids,which serve as the carrier of genetic information.Herein,we reveal the intrinsic mechanism of chiral selection of L-aa and D-Nu from the perspective of chemical origin of life.This work employed15N-labeled L-aa and performed one-pot synthesis of nucleotide amidate of amino acid (N-aa-NMP) using equal amounts of L-15N-aa and D-14N-aa with D-...  相似文献   
7.
Although carbon nanozymes have attracted great interest due to their good biocompatibility, low cost,and high stability, designing high-active carbon nanozymes still faces great challenges. Herein, ultrathin nitrogen-doped carbon nanosheets with rich defects(d-NC) were prepared through a high-temperature annealing process, using potassium chloride and ammonium chloride as templates. Owing to the large specific surface area, rich defects and the high exposure of active sites, the proposed d-NC na...  相似文献   
8.
A new concept of lightweight structure,namely amorphous-alloy-reinforced perforated armor(ARPA)consisting of the amorphous alloy coating and perforated metal substrate plate,is proposed.The ballistic performance of the ARPA is investigated numerically.The failure modes of ARPA and projectiles are identified,and the defeating mechanism of the ARPA is explored.It is shown that the amorphous alloy coating is helpful for enhancing the target’s ballistic performance by seriously eroding and fracturing the penetrators.The effects of coating thickness,initial impact velocity and impact angle are also discussed for the target’s ballistic performance.The optimal design of coating thickness may be necessary for enhancing the ballistic resistance of ARPAs.  相似文献   
9.
The drug resistance of chemotherapy is a major challenge to overcome for antineoplastic agents and the reverse of drug resistant is essential for cancer therapy. Herein, we developed a drug delivery system which can simultaneously detect/reverse the drug resistance and perform synergetic treatment of cancer. In this work, we integrated cyanine5(Cy5) modified mi RNA(let-7 i)(Cy5-mi RNA) and platinum onto nano-graphene oxide(NGO)(30-50 nm) platform to achieve simultaneously detection/reversion of ...  相似文献   
10.
Yan He 《中国物理 B》2022,31(11):110502-110502
The transport properties of core-shell nanowires (CSNWs) under interface modulation and confinement are investigated based on the atomic-bond-relaxation (ABR) correlation mechanism and Fermi's golden rule. An analytical expression for the relationship between carrier mobility and interface mismatch strain is derived and the influence of size, shell thickness and alloyed layer on effective mass, band structures, and deformation potential constant are studied. It is found that interface modulation can not only reduce the lattice mismatch to optimize the band alignment, but also participate in the carrier transport for enhancing mobility. Moreover, the underlying mechanism regarding the interface shape dependence of transport properties in CSNWs is clarified. The great enhancement of electron mobility suggests that the interface modulation may become a potential pathway to improving the performance of nanoelectronic devices.  相似文献   
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