Complex impedance spectra of the low- and high-resistance states Au/NiO/Pt ITO/TiO2/ITO heterostructures were studied to probe characteristics conducting filaments (CFs). Different types CFs compared both qualitatively quantitatively. It was demonstrated that important information CFs, including behavior as well position degree rupture, can be obtained by analysis complex data. We further employed this tool explore resistive switching effect in HfO2 based fabricated different methods,...

Wurtzite gallium nitride (GaN) has great potential for high-frequency and high-power applications due to its excellent electrical thermal transport properties.However, enhancing the performance of GaN-based power electronics relies on heavy doping.Previous studies showed that electron-phonon interactions have strong effects lattice conductivity GaN Fröhlich interaction.Surprisingly, our investigation reveals weak n-type at ultra-high electron concentrations impact interaction can be...

As a wide bandgap semiconductor, diamond holds both excellent electrical and thermal properties, making it highly promising in the industry. However, its hole mobility is relatively low dramatically decreases with increasing temperature, which severely limits further applications. Herein, we proposed that can be efficiently enhanced via slight compressive shear strain along [100] direction, while improvement [111] direction marginal. This impressive distinction attributed to deformation...

Two-dimensional gallium nitride (2D-GaN) has great potential in power electronics and optoelectronics. Heat dissipation is a critical issue for these applications of 2D-GaN. Previous studies have shown that higher-order phonon–phonon scattering extremely strong effects on the lattice thermal conductivity (κlat) 2D-GaN, with fourth-order interatomic force constants (4th-IFCs) calculated using experienced atomic displacement finite difference method. In this work, it found 4th-IFCs 2D-GaN are...

Here, we report the co-substitution of Fe and Co for Ni atoms on metamagnetic behavior, martensitic transformation, transport magnetocaloric properties in Ni45(Co1−xFex)5Mn36.6In13.4 (x = 0∼0.05) alloys. It is found that introduction stabilizes phase shifts temperature (TM) to higher temperature. Meanwhile, Curie TC parent notably decreases. Upon doping, low magnetization keeps nearly unchanged while slightly As a result, Fe-doped samples maintain strong behavior show great MR MCE an...

The resistive switching behaviors of indium (In)/Nb:SrTiO3 (NSTO) with different metal/semiconductor contacts are investigated. In electrodes the Schottky fabricated on NSTO surface using direct current reactive magnetron sputtering, and fresh is directly pressed to form Ohmic contact. device one barrier displays a normal bipolar (BRS) behavior, while two barriers shows an abnormal BRS behavior. results demonstrate that injection trapping or detrapping carriers near interface between metal...

The crystal structure and magnetoresistance of are investigated. La1-xNaxMnO3 crystallizes in a rhombohedrally distorted perovskite exhibits sharp ferromagnetic transition as well negative at around room temperature. On the basis alternating-current susceptibility resistivity measurements comparison with compounds, it is proposed that Na doping tends to drive system from regime characterized by strong Hund coupling electron-phonon one weak coupling.

A systematic study on photovoltaic effects has been performed for the Schottky junction Au/SrTiO3:0.05 wt %Nb, resistance of which can be tuned, by applied electric pulses, between ∼1 and ∼200 MΩ. It is found that, despite great change in resistance, photocurrent across constant when power wavelength incident light are fixed. The corresponding barrier, deduced from photoresponse data ∼1.5 eV, independent resistance. This result suggests invariance interfacial barrier during switching...

Current-voltage characteristics and colossal electroresistance (CER) have been experimentally investigated in the temperature range from 293 to 454 K for Schottky junctions Au/SrTiO3:0.5 wt % Nb Au/SrTiO3:0.05 Nb. Both show electron tunneling-dominated transport behavior. Postannealing of SrTiO3:0.05 oxygen atmosphere causes a transition behavior tunneling thermionic emission. The CER effect appears with dominated by greatly weakens when emission prevails after postannealing. This result...

At the interface of LaAlO3/SrTiO3 with film thickness 3 unit cells or greater, a reproducible electric-field-induced bipolar resistance switching interfacial conduction is observed on nanometer scale by biased conducting atomic force microscopy under vacuum environment. The behavior suggested to be an intrinsic feature SrTiO3 single crystal substrates, which mainly originates from modulation oxygen ion transfer in surface external electric field vicinity interface, whereas LaAlO3 acts as...

Dynamic processes of resistance switching have been systemically investigated for the Ti/HfO2/Pt bipolar devices. Different transient characteristics were observed in set and reset processes. The process consisted a waiting step following abrupt transition, whereas demonstrated gradual change. Nonlinear dependence time on pulse voltage was explained by thermally accelerated dielectric breakdown local regions. accumulation dissipation effects different treatments strongly supported proposed...

4H-silicon carbide (4H-SiC) possesses a high Baliga figure of merit, making it promising material for power electronics. However, its applications are limited by low hole mobility. Herein, we found that the mobility 4H-SiC is mainly strong interband electron-phonon scattering using mode-level first-principles calculations. Our research indicates applying compressive strain can reverse sign crystal-field splitting and change ordering electron bands close to valence band maximum. Therefore,...

Transition-metal dichalcogenides (TMDs) have great potential in the field of thermoelectric conversion due to their remarkable transport properties. However, large lattice thermal conductivity TMDs is a fundamental bottleneck achieving high efficiency. The Janus structures are formed by replacing one chalcogenide layers primitive cell MX2 (M═Mo and W, X═S Se) with other chalcogen elements. In this work, we perform comprehensive first-principles investigation on phonon bulk materials MSSe. It...

A comparable study of the microstructure and magnetic properties was performed for magnetite films deposited on (100)-oriented MgO SrTiO3 (STO) substrates. The growth strained high quality Fe3O4 confirmed by x-ray diffraction analysis Raman spectroscopy measurements. surface morphology two were found to be obviously different. Moreover, a stripelike domain structure observed in film STO. Substrate-induced strain is believed responsible these observations, which significantly affects...

We performed a systematic investigation on the dynamic behavior of conduction filaments (CFs) in WO3-x-based devices. It was found that electric forming produced an structure consisted conductive channel (virtual cathode) started from cathode and insulating band surrounding anode. Both virtual region varied with repeated resistance switching. Set/reset operation affected device mainly by modifying CF, which formed setting process together halo separated it cathode. The exhibited sudden...

Maxwell relation and mean-field approximation are chosen to estimate the total entropy change magnetic change, respectively. The experimental results exactly consonant with theoretical results. Consequently, changes make up majority of lattice small. giant magnetocaloric effect in MnAs is clarified. According thermodynamics discussion, modulus compression stress at TC decrease dramatically. Therefore, magneto-structural phase transition a kind soft mode.

Resistance switching property induced by pulsed electric-field in metal-oxide-metal sandwiches attracted much interest due to its potential application nonvolatile memory devices. In this paper, the influence of crystallinity La0.7Ca0.3MnO3 (LCMO) film on resistance Ag-LCMO-Pt has been investigated. LCMO films were grown Pt/Ti/SiO2/Si substrates using laser deposition technique at different substrate temperatures. The characterized x-ray diffraction, atomic force microscopy, transmission...

We studied the resistive switching (RS) effect in LaAlO3/Nb:SrTiO3 heterostructures at different temperatures with AC impedance technique addition to conventional I–V measurements. It was demonstrated that bipolar RS originates from interface and resistance capacitance states are controlled by filling status of traps. A model based on variation trap state proposed explain thermal history dependent electronic transport behavior. This work demonstrates key role transport.

Photoresponse in the Au/SrTiO3:0.5 wt % Nb Schottky junction with an electric field–tunable resistance between ∼70 kΩ and ∼900 MΩ has been experimentally studied. The most remarkable observation is strong dependence of open-circuit photovoltage on invariance short-circuit photocurrent during switching. These results, combined a theoretical calculation based equivalent circuit model consisting diode parallel resistor, suggest occurrence filamentary conductive channels across interface under...

The transmittance of tungsten oxides can be adjusted by oxygen vacancy (Vo) concentration due to its electrochromic property. Here, we report an in-situ observation resistive switching phenomenon in the oxygen-deficient WO3-x planar devices. Besides directly identifying formation/rupture dark-colored conductive filaments oxide layer, stripe-like device demonstrated self-regulated behavior during endurance testing, resulting highly consistent parameters after a stabilizing process. For very...