In situ TEM investigation of oxygen migration as a key mechanism for resistive switching in Pr0.7Ca0.3MnO3

Niobium nitride thin films for very low temperature resistive thermometry

We investigate thin film resistive thermometry based on metal-to-insulator-transition (niobium nitride) materials down to very low temperature. The variation of the NbN thermometer resistance have been calibrated versus temperature and magnetic field. High sensitivity in tempertaure variation detection is demonstrated through efficient temperature coefficient of resistance. The nitrogen content of the niobium nitride thin films can be tuned to adjust the optimal working temperature range. In the present experiment, we show the versatility of the NbN thin film technology through applications in…

二维材料忆阻器中聚合物残留的非易失性阻变

Non-Volatile Resistive Switching of Polymer Residues in 2D Material Memristors

该研究揭示二维材料忆阻器中的阻变可能源于制造过程中残留的聚合物，而非二维材料本身，并强调需通过参考结构和原子尺度表征来正确评估二维材料作为开关层的真实潜力。

Asymmetry-induced resistive switching in Ag-Ag$_{2}$S-Ag memristors enabling a simplified atomic-scale memory design

Prevailing models of resistive switching arising from electrochemical formation of conducting filaments across solid state ionic conductors commonly attribute the observed polarity of the voltage-biased switching to the sequence of the active and inert electrodes confining the resistive switching memory cell. Here we demonstrate equivalent, stable switching behavior in metallic Ag-Ag$_{2}$S-Ag nanojunctions at room temperature. Our experimental results and numerical simulations reveal that the polarity of the switchings is solely determined by the geometrical asymmetry of the electrode surface…

Bipolar resistive switching in amorphous titanium oxide thin films

Using isothermal and temperature-dependent electrical measurements, we investigated the resistive switching mechanism of amorphous titanium oxide thin films deposited by a plasma-enhanced atomic layer deposition method between two aluminum electrodes. We found a bipolar resistive switching behavior in the high temperature region (> 140 K), and two activation energies of shallow traps, 0.055 eV and 0.126 eV in the ohmic current regime. We also proposed that the bipolar resistive switching of amorphous TiO2 thin films is governed by the transition of conduction mode from a bulk-limited SCLC mode…

TiTe2点接触电导中电阻开关与二极管效应的观测

Observation of resistive switching and diode effect in the conductivity of TiTe2 point contacts

本研究测量了TiTe2点接触的电学特性，观测到电荷密度波特征、电阻开关现象及独特的类二极管效应，表明TiTe2在开发非易失性ReRAM等纳米技术方面具有潜力。

Inherent stochasticity of superconductive-resistive switching in nanowires

Hysteresis in the current-voltage characteristic in a superconducting nanowire reflects an underlying bistability. As the current is ramped up repeatedly, the state switches from a superconductive to a resistive one, doing so at random current values below the equilibrium critical current. Can a single phase-slip event somewhere along the wire--during which the order-parameter fluctuates to zero--induce such switching, via the local heating it causes? We address this and related issues by constructing a stochastic model for the time-evolution of the temperature in a nanowire whose ends are mai…

通过焦耳热实现FeRh的高速变磁电阻开关

High-speed metamagnetic resistive switching of FeRh through Joule heating

针对FeRh变磁有序转变在高性能计算器件中的应用潜力，本研究通过焦耳热实现其电控制，结合有限元模拟揭示热力学机制，测得电流达60 mA时转变温度降150 K，还展示了高速类忆阻器行为及优异性能参数。

Adsorbate Migration Effects on Continuous and Discontinuous Temperature-Dependent Transitions in the Quality Factors of Graphene Nanoresonators

We perform classical molecular dynamics simulation to investigate the mechanisms underpinning the unresolved, experimentally-observed temperature-dependent scaling transition in the quality factors of graphene nanomechanical resonators (GNMR). Our simulations reveal that the mechanism underlying this temperature scaling phenomenon is the out-of-plane migration of adsorbates on GNMRs. Specifically, the migrating adsorbate undergoes frequent collisions with the GNMR, which strongly influences the resulting mechanical oscillation, and thus the quality factors. We also predict a discontinuous tran…

Charge migration mechanisms in the DNA at finite temperature revisited; from quasi-ballistic to subdiffusive transport

Various charge migration mechanisms in the DNA are studied within the framework of the Peyrard-Bishop-Holstein model which has been widely used to address charge dynamics in this macromolecule. To analyze these mechanisms we consider characteristic size and time scales of the fluctuations of the electronic and vibrational subsystems. It is shown, in particular, that due to substantial differences in these timescales polaron formation is unlikely within a broad range of temperatures. We demonstrate that at low temperatures electronic transport can be quasi-ballistic. For high temperatures, we p…

Microscopic origin of bipolar resistive switching of nanoscale titanium oxide thin films

We report a direct observation of the microscopic origin of the bipolar resistive switching behavior in nanoscale titanium oxide films. Through a high-resolution transmission electron microscopy, an analytical TEM technique using energy-filtering transmission electron microscopy and an in situ x-ray photoelectron spectroscopy, we demonstrated that the oxygen ions piled up at top interface by an oxidation-reduction reaction between the titanium oxide layer and the top Al metal electrode. We also found that the drift of oxygen ions during the on/off switching induced the bipolar resistive switch…

使用自洽相场方法对介电薄膜中导电通道的电热计算研究：探寻电阻开关的物理起源

An electro-thermal computational study of conducting channels in dielectric thin films using self-consistent phase-field methodology: A view toward the physical origins of resistive switching

本文采用自洽相场方法模拟介电薄膜中导电通道的形成与湮灭，揭示电场与温度耦合下电荷畴演化及电阻开关的物理机制。

Physics inspired compact modelling of BiFeO$_3$ based memristors for hardware security applications

With the advent of the Internet of Things, nanoelectronic devices or memristors have been the subject of significant interest for use as new hardware security primitives. Among the several available memristors, BiFe$\rm O_{3}$ (BFO)-based electroforming-free memristors have attracted considerable attention due to their excellent properties, such as long retention time, self-rectification, intrinsic stochasticity, and fast switching. They have been actively investigated for use in physical unclonable function (PUF) key storage modules, artificial synapses in neural networks, nonvolatile resisti…