Layered Antiferromagnetism Induces Large Negative Magnetoresistance in the van der Waals Semiconductor CrSBr
Evan J. Telford, Avalon H. Dismukes, Kihong Lee, Minghao Cheng, Andrew Wieteska, Amymarie K. Bartholomew, Yu-Sheng Chen, Xiaodong Xu, Abhay N. Pasupathy, Xiaoya… 展开作者
Evan J. Telford, Avalon H. Dismukes, Kihong Lee, Minghao Cheng, Andrew Wieteska, Amymarie K. Bartholomew, Yu-Sheng Chen, Xiaodong Xu, Abhay N. Pasupathy, Xiaoyang Zhu, Cory R. Dean, Xavier Roy
The recent discovery of magnetism within the family of exfoliatable van der Waals (vdW) compounds has attracted considerable interest in these materials for both fundamental research and technological applications. However current vdW magnets are limited by their extreme sensitivity to air, low ordering temperatures, and poor charge transport properties. Here we report the magnetic and electronic properties of CrSBr, an air-stable vdW antiferromagnetic semiconductor that readily cleaves perpendicular to the stacking axis. Below its Néel temperature, $T_N = 132 \pm 1$ K, CrSBr adopts an A-type antiferromagnetic structure with each individual layer ferromagnetically ordered internally and the layers coupled antiferromagnetically along the stacking direction. Scanning tunneling spectroscopy and photoluminescence (PL) reveal that the electronic gap is $Δ_E = 1.5 \pm 0.2$ eV with a corresponding PL peak centered at $1.25 \pm 0.07$ eV. Using magnetotransport measurements, we demonstrate strong coupling between magnetic order and transport properties in CrSBr, leading to a large negative magnetoresistance response that is unique amongst vdW materials. These findings establish CrSBr as a promising material platform for increasing the applicability of vdW magnets to the field of spin-based electronics.
Using temperature-dependent magnetoresistance and magnetization measurements on Fe/Cr multilayers that exhibit pronounced giant magnetoresistance (GMR), we have found evidence for the presence of a glassy antiferromagnetic (GAF) phase. This phase reflects the influence of interlayer exchange coupling (IEC) at low temperature (T < 140K) and is characterized by a field-independent glassy transition temperature, Tg, together with irreversible behavior having logarithmic time dependence below a "de Almeida and Thouless" (AT) critical field line. At room temperature, where the GMR effect is still r…
Controlling magnetism in low dimensional materials is essential for designing devices that have feature sizes comparable to several critical length scales that exploit functional spin textures, allowing the realization of low-power spintronic and magneto-electric hardware. [1] Unlike conventional covalently-bonded bulk materials, van der Waals (vdW)-bonded layered magnets [2-4] offer exceptional degrees of freedom for engineering spin textures. [5] However, their structural instability has hindered microscopic studies and manipulations. Here, we demonstrate nanoscale structural control in the …
The magnetic tunnel junction (MTJ) is a backbone device for spintronics. Realizing next generation energy efficient MTJs will require operating mechanisms beyond the standard means of applying magnetic fields or large electrical currents. Here, we demonstrate a new concept for programmable MTJ operation via strain control of the magnetic states of CrSBr, a layered antiferromagnetic semiconductor used as the tunnel barrier. Switching the CrSBr from antiferromagnetic to ferromagnetic order generates a giant tunneling magnetoresistance ratio without external magnetic field at temperatures up to ~…
Transport and magnetoresistance measurements are performed on metallic, high-carrier density YTiO3-CaTiO3 superlattices as a probe towards the investigation of an emergent magnetic order of YTiO3. On varying the thickness of YTiO3 while keeping the CaTiO3 layer thickness constant in the superlattices, a low-temperature upturn in sheet-resistance, a non-Fermi liquid-like charge transport and positive magnetoresistance are observed. Analyses of the origin of such effects suggest that a unique antiferromagnetic order is realized in the ultra-thin, epitaxially strained YTiO3 layers, which corrobor…
Magnetic van der Waals (vdW) materials offer a fantastic platform to investigate and exploit rich spin configurations stabilized in reduced dimensions. One tantalizing magnetic order is the interlayer antiferromagnetism in A-type vdW antiferromagnet, which may be effectively modified by the magnetic field, stacking order and thickness scaling. However, atomically revealing the interlayer spin orientation in the vdW antiferromagnet is highly challenging, because most of the material candidates exhibit an insulating ground state or instability in ambient conditions. Here, we report the layer-dep…
Single crystal of the binary equi-atomic compound GdBi crystallizing in the rock salt type cubic crystal structure with the space group $Fm\bar{3}m$ has been grown by flux method. The electrical and magnetic measurements have been performed on well oriented single crystals. The antiferromagnetic ordering of the Gd moments is confirmed at $T_{\rm N} = 27.5$~K. The magnetization measurement performed at $2$~K along the principal crystallographic direction [100] did not show any metamagnetic transition and no sign of saturation up to $7$~T. Zero field electrical resistivity reveals a sharp drop a…
Ferromagnetism above 200 K in organic-ion intercalated CrSBr
CIC nanoGUNE（纳米技术联合研究中心）；UPV/EHU（巴斯克地区理工大学）；CSIC-UPV/EHU（西班牙国家科研委员会-巴斯克地区理工大学）；Izmir Institute of Technology（伊兹密尔理工大学）；IKERBASQUE（伊克尔巴斯基奎基金会）；Universitat de València（瓦伦西亚大学）
We investigate electronic transport through exfoliated multilayers of CrSBr, a 2D semiconductor that is attracting attention because of its magnetic properties. We find an extremely pronounced anisotropy that manifests itself in qualitative and quantitative differences of all quantities measured along the in-plane \textit{a} and \textit{b} crystallographic directions. In particular, we observe a qualitatively different dependence of the conductivities $σ_a$ and $σ_b$ on temperature and gate voltage, accompanied by orders of magnitude differences in their values ($σ_b$/$σ_a \approx 3\cdot10^2-1…
The rare-earth nickelates (RNiO3) exhibit interesting phenomena such as unusual antiferromagnetic order at wavevector q = (1/2, 0, 1/2) and a tunable insulator-metal transition that are subjects of active research. Here we present temperature-dependent transport measurements of the resistivity, magnetoresistance, Seebeck coefficient, and Hall coefficient (RH) of epitaxial SmNiO3 thin films with varying oxygen stoichiometry. We find that from room temperature through the high temperature insulator-metal transition, the Hall coefficient is hole-like and the Seebeck coefficient is electron-like. …
We observed the coexistence of superconductivity and antiferromagnetic order in the single-crystalline ternary pnictide HoPdBi, a plausible topological semimetal. The compound orders antiferromagnetically at $T_N =$1.9 K and exhibits superconductivity below $T_c =$0.7 K, which was confirmed by magnetic, electrical transport and specific heat measurements. The specific heat shows anomalies corresponding to antiferromagnetic ordering transition and crystalline field effect, but not to superconducting transition. Single-crystal neutron diffraction indicates that the antiferromagnetic structure is…
Enabling Electrical Readout of Néel vector reversal in a van der Waals Antiferromagnet
Carnegie Mellon University（卡内基梅隆大学）；The University of Texas at Dallas（达拉斯大学）；Kansas State University（堪萨斯州立大学）；National Institute for Materials Science（国立材料研究所）
How to realize applicably appreciated functionalities based on the coupling between charge and spin degrees of freedom is still a challenge in the field of spintronics. For example, anisotropic magnetoresistance (AMR) effect is utilized to read out the information stored by various magnetic structures, which usually originates from atomic spin-orbit coupling (SOC). However, the application of AMR in antiferromagnet-based spintronics is still hindered by rather small AMR value. Here, we discover a colossal AMR effect during the field-induced metal-to-insulator transition (MIT) in a nearly Dirac…
Investigation of the oxygen-deficient 112-type ordered oxides of the type LnBaCoMnO5+δ(Ln = Nd, Eu) evidences certain unusual magnetic behavior at low temperatures, compared to the LnBaCo2O5+δcobaltites. One observes that the substitution of manganese for cobalt suppresses the ferromagnetic state and induces strong antiferromagnetic interactions. Importantly, NdBaCoMnO5.9 depicts a clear paramagnetic to antiferromagnetic type transition around 220 K, whereas for EuBaCoMnO5.7 one observes an unusual magnetic behavior below 177 K which consists of ferromagnetic regions embedded in an antiferroma…
