A new proposal is given to achieve high degree of magnetoresistance (MR) in a magnetic quantum device where two magnetic layers are separated by a non-magnetic (NM) quasiperiodic layer that acts as a spacer. The NM spacer is chosen in the form of well-known Aubry-André or Harper (AAH) model which essentially gives the non-trivial features in MR due to its gaped spectrum and yields the opportunities of controlling MR selectively by tuning the AAH phase externally. We also explore the role of dephasing on magnetotransport to make the model more realistic. Finally, we illustrate the experimental possibilities of our proposed quantum system.
Observation of spin-orbit magnetoresistance in metallic thin films on magnetic insulators
由Rashba自旋轨道相互作用引起的磁阻效应被预测，但尚未观察到，在由正常金属和铁磁绝缘体组成的双层膜。在这里，我们提出了一个实验观察这种新型的自旋-轨道磁电阻（SOMR）效应的双层结构Cu[Pt]/Y3 Fe 5 O 12（YIG），其中Cu/YIG界面装饰有纳米尺寸的Pt岛。这种新的MR显然不是由体自旋-轨道相互作用引起的，因为Cu中的自旋-轨道相互作用可以忽略，Pt岛的不连续性。当Pt岛不存在或远离Cu/YIG界面时，SOMR消失，因此我们可以明确地将其归因于Pt装饰增强的界面处的Rashba自旋轨道相互作用。数值模拟结果与SOMR实验结果在磁场的角度依赖性和Cu厚度依赖性方面一致。我们的研究结果表明，实现自旋操纵的接口工程。
Extraordinary magnetoresistance (EMR) is a geometric magnetoresistance effect occurring in hybrid devices consisting of a high-mobility material joined by a metal. The change in resistance can exceed 107% at room temperature when a magnetic field of 5 T is applied. Magnetic field sensors based on EMR hold the potential formeasuring weak magnetic fields with an unprecedented sensitivity, yet, to date this potential is largely unmet. In this work, we provide an extensive review of the current state-of-the-art in EMR sensors with a focus on the hybrid device geometries, the constituent material p…
Strain Tuning of Orbital-Driven Giant Magnetoresistance in van der Waals ferrimagnet Mn$_3$Si$_2$Te$_6$
Institute for Solid State Physics, The University of Tokyo（东京大学固体离子体研究所）；The University of Tokyo（东京大学）；Department of Physics and Astronomy, The University of Manchester（曼彻斯特大学物理与天文学系）；The University of Manchester（曼彻斯特大学）；Department of Physics, Institute of Science Tokyo（东京科学大学物理系）；Institute of Science Tokyo（东京科学大学）
Disorder-induced magnetoresistance (MR) effect is quadratic at low perpendicular magnetic fields and linear at high fields. This effect is technologically appealing, especially in the two-dimensional (2D) materials such as graphene, since it offers potential applications in magnetic sensors with nanoscale spatial resolution. However, it is a great challenge to realize a graphene magnetic sensor based on this effect because of the difficulty in controlling the spatial distribution of disorder and enhancing the MR sensitivity in the single-layer regime. Here, we report a room-temperature colossa…
Although the development of spintronic devices has advanced significantly over the past decade with the use of ferromagnetic materials, the extensive implementation of such devices has been limited by the notable drawbacks of these materials. Antiferromagnets claim to resolve many of these shortcomings leading to faster, smaller, more energy-efficient, and more robust electronics. Antiferromagnets exhibit many desirable properties including zero net magnetization, imperviousness to external magnetic fields, intrinsic high-frequency dynamics with a characteristic precession frequency on the ord…
Floquet engineering is the concept of tailoring a system by a periodic drive. It has been very successful in opening new classes of Hamiltonians to the study with ultracold atoms in optical lattices, such as artificial gauge fields, topological band structures and density-dependent tunneling. Furthermore, driven systems provide new physics without static counterpart such as anomalous Floquet topological insulators. In this review article, we provide an overview of the exciting developments in the field and discuss the current challenges and perspectives.
