No abstract

Conventional von Newmann-based computers face severe challenges in the processing and storage of the large quantities of data being generated in the current era of “big data.” One of the most promising solutions to this issue is the development of an artificial neural network (ANN) that can process and store data in a manner similar to that of the human brain. To extend the limits of Moore’s law, memristors, whose electrical and optical behaviors closely match the biological response of the human brain, have been implemented for ANNs in place of the traditional complementary metal-oxide-semiconductor (CMOS) components. Based on their different operation modes, we classify the memristor family into electronic, photonic, and optoelectronic memristors, and review their respective physical principles and state-of-the-art technologies. Subsequently, we discuss the design strategies, performance superiorities, and technical drawbacks of various memristors in relation to ANN applications, as well as the updated versions of ANN, such as deep neutral networks (DNNs) and spike neural networks (SNNs). This paper concludes by envisioning the potential approaches for overcoming the physical limitations of memristor-based neural networks and the outlook of memristor applications on emerging neural networks.

We propose an efficient protocol for measuring the concurrence of arbitrary twophoton pure entangled state with the help of the photonic Faraday rotation. In the protocol, the concurrence of the photonic entangled state can be conversed into the total success probability for picking up the odd-parity photonic state. For completing the measurement task, we require some auxiliary three-level atoms, which are trapped in the low-quality cavities. Our protocol can be well realized under current experimental conditions. Moreover, under practical imperfect atom state detection and photonic Faraday rotation conditions, our protocol can also work well.Based on these features, our protocol may be useful in current quantum information processing.

Hybrid entangled state (HES) is a new type of entanglement, which combines the advantages of an entangled polarization state and an entangled coherent state. HES is widely discussed in the applications of quantum communication and computation. In this paper, we propose three entanglement concentration protocols (ECPs) for Bell-type HES, W-type HES, and cluster-type HES, respectively. After performing these ECPs, we can obtain the maximally entangled HES with some success probability. All the ECPs exploit the single coherent state to complete the concentration. These protocols are based on the linear optics, which are feasible in future experiments.

A linearized tuning varactor for the voltage controlled oscillator (VCO) is proposed in this paper. The capacitance-voltage (C-V) curve is linearized by combining an accumulation MOSFET (AMOS) and PMOS in parallel to form the varactor. Two ring voltage controlled oscillators (ring VCOs) are fabricated and measured with a standard 65-nm CMOS process. They are both identical except for the varactor. The first VCO uses the proposed varactor, and the second one is tuned by a conventional AMOSonly varactor for reference. The ring VCO with the proposed varactor operates from 500.5 to 807.6 MHz, and the VCO gain (K VCO ) varies from 183 to 284 MHz/V. Comparing the reference VCO with the AMOS-only varactor, the measured K VCO variability is reduced by 82%. The phase noise is between −89 dBc/Hz and −92 dBc/Hz at 1 MHz offset while dissipating 0.8 mA from a 1.2-V supply.