Decision trees within a molecular memristor.

The logic gate is the basic unit of a digital circuit structure. The operation, memory, I/O, and other reading and writing functions of computer systems require logic circuits. Logic gates based on resistive memory can make existing integrated circuits denser, smaller, faster, and use fewer devices. In this paper, Al/polymethyl methacrylate (PMMA)/egg albumen (EA):Au nanoparticles/PMMA/Al multilayer biological resistive random access memory was prepared based on the natural biological material—egg albumen (EA). The device has bipolar switching behavior, a higher switching current ratio, a lower threshold voltage, and better stability. A circuit based on auxiliary logic is constructed using this device, and the logic functions of AND, OR, NOT, NAND, and NOR are realized. This device provides an effective potential solution for implementing high-performance electronic devices and large-scale integrated circuits.

Oxide based resistive switching memory are the promising candidates for future non-volatile memory according to fast programing, low power operation, scalability and compatibility to the current CMOS process. Among, SiOx single layer resistive switching devices have been widely studied and characterized. The SiOx single layer resistive memory has good compatibility to CMOS fabrication process. However, it can only be programmed under the vacuum or non-oxidized ambient. Also, the previous results reported on SiOx-based memristors indicate that the electroforming and programming voltage is relatively higher than the other dielectric materials and obstructed for low-power applications. In this work, by using SiOx/HfOx stacking engineering, we have developed a low-voltage operation (< 2V) for SiOx-based ReRAM. The results show that with HfOx (3nm) on bottom, the metal-insulator-semiconductor (MIS) structures exhibit resistive switching at low voltage (<2V) and operation in air atmosphere. The added hafnium layer apparently provides the source of proton exchange reaction with conduction bandgap offset reduction for low-voltage (< 2V) RS (Figure 2). Also, we have studied single HfOx-based MIS devices which exhibit bipolar-type resistive switching behaviors with small memory window.Clearly, SiOx/HfOx stacking optimization not only maintains the RS behaviors even in air environment without any programming window degradation, but also further reduces the switching voltage below 2V. Figure 1 shows the results of three different structures, including SiOx single layer memristor, SiOx/HfOx bilayer memristor and HfOx single layer memristor. In terms of operation environment condition, inserting the HfOx layer would help the SiOx memristor to be able to programmed either under a pressure of 1E-4 torr or in the atmosphere. The HfOx single layer memristor has the lowest electroforming voltage of 2.3 V, and which in SiOx/HfOx stacks has been reduced significantly to 5 V comparing which of 14 V for SiOx single layer. For the SiOx/HfOx bilayer, a memory window of 4 decades is achieved and comparable to that of SiOx single layer, and larger than that of single layer HfOx by 2 decades. In terms of operation voltage, the set voltage is reduced from 4V to 2 V and the reset voltage is also suppressed significantly from 10 V to 0.3 V by inserting the 3 nm HfOx layer. Figure 2 shows the TEM images of both SiOx single layer memristor and SiOx/HfOx bilayer memristor. The 3 nm HfOx was deposited on N+ Si wafer at 250 oC by atomic layer deposition followed by 30 nm SiO2 deposition using e-beam evaporator and 160 nm TaN depositing by sputtering. Figure 3. The single layer HfOx-based MIS devices resistive switching behaviors. (a) The electroforming process, resistive switching behaviors in 20 times cycling. (b) The switching voltage (SET/RESET) and states (HRS/LRS) distribution. Figure 1

The microfluidics domain has been progressing rapidly recently, particularly considering its useful applications in the field of biomedicine. This paper presents a novel, microfluidics-based design for four fundamental circuit elements in electronics, namely resistor, inductor, capacitor, and memristor. These widely used passive components were fabricated using a precise and cost-effective xurography technique, which enables the construction of multi-layered structures on foil, with gold used as a conductive material. To complete their assembly, an appropriate fluid was injected into the microfluidic channel of each component: the resistor, inductor, capacitor, and memristor were charged with transformer oil, ferrofluid, NaCl solution, and TiO2 solution, respectively. The electrical performance of these components was determined using an Impedance Analyzer and Keithley 2410 High-Voltage Source Meter instrument and the observed characteristics are promising for a wide range of applications in the field of microfluidic electronics.

Memristor, a combination of memory and resistor, was first proposed as the fourth fundamental passive circuit element. While halide perovskites have emerged as promising materials for memristor devices, organic-inorganic hybrid perovskites face challenges such as hygroscopicity and thermal instability, limiting their long-term applicability. This paper focuses on inorganic halide perovskite quantum dots (IHPQDs), which offer enhanced environmental stability and unique properties, including high tolerance to native defects and ion migration capability. This paper provides a comprehensive review of recent advancements in IHPQDs, covering their crystal structures, synthesis techniques, and operational mechanisms in memristor devices. Unlike previous studies that predominantly explored bulk halide perovskites, we emphasize the role of IHPQDs in resistive switching memory and neuromorphic computing, highlighting their potential for multilevel resistance states and low-power operation. Additionally, this review addresses practical challenges, including thin-film uniformity, charge transport layer integration, and lead-free alternatives, which are critical for the commercialization of IHPQDs-based memristors. By proposing actionable strategies and future research directions, we aim to bridge the gap between fundamental research and real-world applications, positioning IHPQDs as key materials for next-generation electronic devices.Graphical

The memristor (memory resistor) is the fourth passive element of electrical circuits having dynamic resistance with the ability to keep the last level of resistance even after the power supply is interrupted. This article presents a simplified mathematical function with the capability to define the threshold conditions for memristor operation and a new pattern to describe and modeling of the unwanted current leakage in the subthreshold situation for HP TIO2 memristor. These special features provide a more realistic scheme of TIO2 memristor behavior. Our proposed mathematical function is adaptive with the majority of previous prominent works around the ionic drift modeling of HP memristor and is easy to use in SPICE simulators so can be utilized in a wide range of designs and applications. To our best known this is the first research paper in which the issue of subthreshold current leakage modeling of the memristor is addressed.

DNA (Deoxyribonucleic Acid) logic circuit systems provide a powerful arithmetic architecture for the development of molecular computations. DNA nanotechnology, particularly DNA origami, provides a nanoscale addressable surface for DNA logic circuit systems. Although molecular computations based on DNA origami surfaces have received significant attention in research, there are still obstacles to constructing localized scalable DNA logic circuit systems. Here, we developed elementary DNA logic circuits on a DNA origami surface by employing the strand displacement reaction (SDR) to realize the localized scalable DNA logic circuit systems. We showed that the constructed elementary logic circuits can be scaled up to the localized DNA logic circuit systems that perform arbitrary digital computing tasks, including square root functions, full adder and full subtractor. We used a 50% reduction in the number of localized DNA logic components, compared to localized logic systems based on the threshold strategy. We further demonstrated that the localized DNA logic circuit systems for three-satisfiability (3-SAT) problem solving and disease classification can be implemented using the constructed elementary DNA logic circuits. We expect our approach to provide a new design paradigm for the development of molecular computations and their applications in complex mathematical problem solving and disease diagnosis.

A Memristor (memory resistor) is a two terminal non-linear passive element used to relate magnetic flux with respect to electric charge. A Memristor opposes the flow of electric current across a device like a resistor but also remember the last charge that was flowing through it. Memristor is a fourth passive circuit element after inductor ‘L’ resistor ‘R’, and capacitor ‘C. The voltage and current relationship in a memristor is a multivariable function therefore analyzing the circuit is a difficult task. This paper depicts the designing of a memristor model emulator using multisim and studied about its linear and non-linear characteristics.

In this paper, we focus on the effect of processing‐dependent lattice strain on oxygen ion conductivity in ceria based solid electrolyte thin films. This is of importance for technological applications, such as micro‐SOFCs, microbatteries, and resistive RAM memories. The oxygen ion conductivity can be significantly modified by control of lattice strain, to an extent comparable to the effect of doping bulk ceria with cations of different diameters. The interplay of dopant radii, lattice strain, microstrain, anion‐cation near order and oxygen ion transport is analyzed experimentally and interpreted with computational results. Key findings include that films annealed at 600 °C exhibit lattice parameters close to those of their bulk counterparts. With increasing anneal temperature, however, the films exhibited substantial compaction with lattice parameters decreasing by as much as nearly 2% (viz, Δd600–1100 °C: –1.7% (Sc+3) &gt; –1.5% (Gd+3) &gt; –1.2% (La+3)) for the annealing temperature range of 600–1100 °C. Remarkably 2/3rd of the lattice parameter change obtained in bulk ceria upon changing the acceptor diameter from the smaller Sc to larger La, can be reproduced by post annealing a film with fixed dopant diameter. While the impact of lattice compaction on defect association/ordering cannot be entirely excluded, DFT computation revealed that the main effect appears to result in an increase in migration energy and consequent drop in ionic conductivity. As a consequence, it is clear that annealing procedures should be held to a minimum to maintain the optimum level of oxygen ion conductivity for energy‐related applications. Results reveal also the importance to understand the role of electro‐chemo‐mechanical coupling that is active in thin film materials.

Every person with an electronics background will be familiar with the three fundamental circuit elements- the resistor, the capacitor, and the inductor. In 1971, the fourth fundamental circuit element was postulated named as the memristor [1], which is short of memory + resistor. In May 2008, researchers at HP Labs published a paper announcing a model for the physical realization of the memristor. This paper deals with the modeling of the memristor in MATLAB environment and its subsequent applications as a non-volatile digital memory and in arithmetic circuits- adder and multiplier. Here we present the 1-bit non-volatile memory as a flip-flop, 2-bit adder and 2-bit multiplier. With the similar concepts the sizes of flip-flop, adder and multiplier can be increases. The major application can be the elimination of improper shutdown of computers and no data loss.

Attractive electron correlations due to an electron-vibron interaction can overcome the direct Coulomb repulsion of polarons in deformable molecular quantum dots (MQDs). If it happens, a switching appears in the $I\text{\ensuremath{-}}V$ characteristics of the degenerate nonadiabatic molecular bridges weakly coupled with electrodes providing a route to ultrafast ``memristors'' (memory resistors) as the basis for future oscillators, amplifiers and other important circuit elements. Here, we extend our theory of polaronic memristors to adiabatic MQDs strongly coupled with leads to show that the degeneracy of MQD (or multilevel energy structure) along with the polaron-polaron attraction is a vital ingredient of its switching behavior in the strong-coupling regime as well.

In neuromorphic applications, resistive memory solutions (implemented as Resistive Random Access Memory or ReRAM) have significant potential in emulating the desired two-terminal synaptic functionality of real synapses. One of the unique features for the demonstrated ReRAM devices includes conductance modulation, which allows for the implementation of the synaptic weight between neuronal elements. In this paper, we illustrate the multi-resistance level switching capabilities of our unique ReRAM-CMOS hybrid system, which is a demonstration vehicle for implementation of a memristive Dynamic Adaptive Neural Network Array, also known as mrDANNA. Discrete resistance levels have been achieved through application of varying gate voltage and discrete electric pulses in the order of nanoseconds.

Radio frequency (RF) circuit elements that are traditionally considered to be linear frequently exhibit nonlinear properties that affect the intended operation of many other RF systems. Devices such as RF connectors, antennas, attenuators, resistors, and dissimilar metal junctions generate nonlinear distortion that degrades primary RF system performance. The communications industry is greatly affected by these unintended and unexpected nonlinear distortions. The high transmit power and tight channel spacing of the communication channel makes communications very susceptible to nonlinear distortion. To minimize nonlinear distortion in RF systems, specialized circuits are required to measure the low level nonlinear distortions created from traditionally linear devices, i.e., connectors, cables, antennas, etc. Measuring the low-level nonlinear distortion is a difficult problem. The measurement system requires the use of high power probe signals and the capability to measure very weak nonlinear distortions. Measuring the weak nonlinear distortion becomes increasingly difficult in the presence of higher power probe signals, as the high power probe signal generates distortion products in the measurement system. This paper describes a circuit design architecture that achieves 175 dB of dynamic range which can be used to measure low level harmonic distortion from various passive RF circuit elements.

Charge injection transistors and logic circuits

With the rapid development of computer technology, logical circuits play an important role in many fields. Semiconductor transistors, as the basic logic circuit unit of modern computer hardware structure, also encounter more and more technical limitations in the highly integrated field such as computer chips. In order to continue Moore's Law effectively, higher requirements need to be put forward for the basic logic unit. The emergence of memristor opens up a new way to explore advanced computing architecture. This paper presents a MRL- based logic circuit in which input and output logic is provided by high and low voltage. Logic gate circuit elements such as XOR, NAND, NOR are implemented in conjunction with CMOS inverters. Through the construction of basic ratio logic gate, the adder and multiplier is simplified, and the result of signal simulation using LTspice software is completely correct. Finally, a multifunctional logic module is innovatively designed.

Exploring the decision-making process of ensemble learning algorithms in landslide susceptibility mapping: Insights from local and global explainable AI analyses