相关论文: Spin correlations and colossal magnetoresistance i…
Colossal magnetoresistance (CMR) refers to a large change in electrical conductivity induced by a magnetic field in the vicinity of a metal-insulator transition and has inspired extensive studies for decades\cite{Ramirez1997, Tokura2006}.…
The ferrimagnetic insulator Mn3Si2Te6, which features a Curie temperature Tc at 78 K and a delicate yet consequential magnetic frustration, exhibits colossal magnetoresistance (CMR) when the magnetic field is applied along the magnetic hard…
Recent experiments suggest a new paradigm towards novel colossal magnetoresistance (CMR) in a family of materials EuM$_2$X$_2$(M=Cd, In, Zn; X=P, As), distinct from the traditional avenues involving Kondo-RKKY crossovers, magnetic phase…
In the ferrimagnetic semiconductor Mn$_3$Si$_2$Te$_6$, a colossal magnetoresistance (CMR) is observed only when a magnetic field is applied along the magnetic hard axis ($\mathbf{H}\parallel c$). This phenomenon suggests an unconventional…
The n-type HgCr2Se4 exhibits a sharp semiconductor-to-metal transition (SMT) in resistivity accompanying the ferromagnetic order at TC = 106 K. Here, we investigate the effects of pressure and magnetic field on the concomitant SMT and…
The magnetic, transport, and structural properties of (Ga,Cr)As are reported. Zincblende Ga$_{1-x}$Cr$_{x}$As was grown by low-temperature molecular beam epitaxy (MBE). At low concentrations, x$\sim$0.1, the materials exhibit unusual…
Combined resistance noise and muon-spin relaxation ($\mu$SR) measurements of the ferromagnetic semiconductor HgCr$_2$Se$_4$ suggest a degree of magnetoelectric coupling and provide evidence for the existence of isolated magnetic polarons.…
Optical conductivity data s(w) of the colossal magneto-resistance (CMR) pyrochlore Tl2Mn2O7 are presented as functions of temperature (T) and externalmagnetic field (B). Upon cooling and upon applying B near the Curietemperature, where the…
We discuss magnetotransport in a low density electron gas coupled to spin fluctuations near and above a ferromagnetic transition. Provided the density is low enough ($n \lesssim 1/\xi^{3}(T)$, with $\xi(T)$ the ferromagnetic correlation…
A detailed study of poly- and single crystalline samples of the normal spinel HgCr2S4 is reported. The structural refinement reveals enhanced values of the atomic displacements suggesting closeness to a structural instability.…
The temperature and voltage dependence of spin transport is theoretically investigated in a new type of magnetic tunnel junction, which consists of two ferromagnetic outer electrodes separated by a ferromagnetic barrier and a nonmagnetic…
Here, we report spin-selective transport and exceptionally large positive junction magnetoresistance (JMR) in sputter-deposited Mn$_2$CoAl/native-SiO$_2$/p-Si heterostructures. Highly ordered inverse-Heusler Mn$_2$CoAl thin films with…
We report on the spin-Hall magnetoresistance (SMR) and spin Seebeck effect (SSE) in multiferroic CoCr2O4 (CCO) spinel thin films with Pt contacts. We observe a large enhancement of both signals below the spin-spiral (Ts = 28 K) and the spin…
We present a detailed study of the dielectric and charge transport properties of the antiferromagnetic cubic spinel HgCr2S4. Similar to the findings in ferromagnetic CdCr2S4, the dielectric constant of HgCr2S4 becomes strongly enhanced in…
Spin semimetals are a recently discovered new class of spintronic materials, which exhibit a band gap in one spin channel while a semimetallic feature in the other and thus allows for tunable spin transport. Here, we present experimental…
Half-metals are ferromagnets hosting spin-polarized conducting carriers and crucial for spintronics applications. The chromium spinel HgCr2Se4 represents a unique type of half-metal, which features a half-metal to semiconductor transition…
Colossal magnetoresistance (CMR) is commonly observed in magnetic semiconductors when an external magnetic field is applied, usually accompanied by anomalous resistivity peaks or humps which were previously considered as evidence of a…
We investigate spin and thermal transport near the N\'{e}el transition temperature $T_N$ in three dimensions, by numerically analyzing the classical antiferromagnetic $XXZ$ model on the cubic lattice, where in the model, the anisotropy of…
To study non-Heisenberg effects in the vicinity of spin crossover in strongly correlated electron systems we derive an effective low-energy Hamiltonian for the two-band Kanamori model. It contains Heisenberg high-spin term proportional to…
We report the observation of a frequency shift and splitting of the electron spin resonance (ESR) mode of the low-dimensional S=1/2 frustrated antiferromagnet Cs2CuCl4 in the spin-correlated state below the Curie-Weiss temperature 4 K but…