相关论文: Contact effects on transport in magnetite, an arch…
We present a theoretical study of the ballistic magnetoresistance in Ni contacts using first-principles, atomistic electronic-structure calculations. In particular we investigate the role of defects in the contact region in order to explain…
The transition from tunneling to metallic contact between two surfaces does not always involve a jump, but can be smooth. We have observed that the configuration and material composition of the electrodes before contact largely determines…
The magnetoresistance (MR) effect in metallic atomic-sized contacts is studied theoretically by means of first-principle electronic structure calculations. We consider three-atom chains formed from Co, Cu, Si, and Al atoms suspended between…
A common issue in low temperature measurements of enhancement-mode metal-oxide-semiconductor (MOS) field-effect transistors (FETs) in the low electron density regime is the high contact resistance dominating the device impedance. In that…
We present results for a model that describes a quantum point contact. We show how electron-electron correlations, within the unrestricted Hartree-Fock approximation, generate a magnetic moment in the point contact. Having characterized the…
This a review article, which presents a general framework for the analysis of interatomic magnetic interactions in the spin-density-functional theory, which is based on the magnetic force theorem, make a link with the models for…
Magnetite (Fe3O4) based tunnel junctions with turret/mesa structure have been investigated for different barrier materials (SrTiO3, NdGaO3, MgO, SiO2, and Al2O(3-x)). Junctions with a Ni counter electrode and an aluminium oxide barrier…
There is an increasing amount of literature concerning electronic properties of graphene close to the neutrality point. Many experiments continue using the two-probe geometry or invasive contacts or do not control samples' macroscopic…
Magnetoquantum oscillations of resistance as functions of the potential difference applied across the contact are studied for metallic point contacts made of $Al$ and $Be$. The amplitude of resistance oscillations in a magnetic field…
We report a systematic study of the bias-dependent contact resistance in rubrene single-crystal field-effect transistors with Ni, Co, Cu, Au, and Pt electrodes. We show that the reproducibility in the values of contact resistance strongly…
In ultra-thin two-dimensional (2-D) materials, the formation of ohmic contacts with top metallic layers is a challenging task that involves different processes than in bulk-like structures. Besides the Schottky barrier height, the transfer…
Chemiresistive materials, which alter their electrical resistance in response to interactions with surrounding chemicals, are valued for their robustness, rapid detection ability and high sensitivity. Recent research has revealed that the…
Transition metal oxides (TMOs) exhibit many emergent phenomena ranging from high-temperature superconductivity and giant magnetoresistance to magnetism and ferroelectricity. In addition, when TMOs are interfaced with each other, new…
We investigate the magnetic properties of archetypal transition-metal oxides MnO, FeO, CoO and NiO under very high pressure by x-ray emission spectroscopy at the K\beta line. We observe a strong modification of the magnetism in the megabar…
The effective barrier height between an electrode and a ferroelectric (FE) depends on both macroscopic electrical properties and microscopic chemical and electronic structure. The behavior of a prototypical electrode/FE/electrode structure,…
We report the temperature dependence of transport and magnetic properties of La$_{1-x}$Ca$_x$VO$_3$ for x = 0.0, 0.1, 0.2, 0.3, 0.4 and 0.5. The system exhibits an insulator-to-metal transition concomitant with an…
The resistivity in the ferromagnetic state of flux-grown La_{2/3}(Pb,Ca)_{1/3}MnO_3 single crystals, measured in magnetic fields up to 7 T, reveals a strong quadratic temperature dependence at and above 50 K. At lower temperatures, this…
We studied spin transport in four organic semiconductors (OSCs) with different electronic properties, with Fe and Co as the top and bottom ferromagnetic (FM) contacts, respectively. Magnetoresistance (MR) effects were observed up to room…
Magneto-resistance is a physical effect of great fundamental and industrial interest since it is the basis for the magnetic field sensors used in computer read-heads and Magnetic Random Access Memories. As device dimensions are reduced,…
Recent reports highlight the potential of tin-based perovskite semiconductors for high-performance p-type field-effect transistors (FETs) with mobilities exceeding 20 cm2V-1s-1. However, these high mobilities--often obtained via two-probe…