A5100338023- Magnetic properties of thin films
- Physics of Superconductivity and Magnetism
- Characterization and Applications of Magnetic Nanoparticles
- Cosmology and Gravitation Theories
- ZnO doping and properties
- Advanced Memory and Neural Computing
- Theoretical and Computational Physics
- Multiferroics and related materials
- Astronomical Observations and Instrumentation
- Magneto-Optical Properties and Applications
- Quantum and electron transport phenomena
- Astronomy and Astrophysical Research
- Solar and Space Plasma Dynamics
- Adaptive optics and wavefront sensing
- Particle Accelerators and Free-Electron Lasers
- Acoustic Wave Resonator Technologies
- Pulsars and Gravitational Waves Research
- Optical Systems and Laser Technology
- Black Holes and Theoretical Physics
- Geophysics and Gravity Measurements
- Financial Risk and Volatility Modeling
- Magnetic and transport properties of perovskites and related materials
- Silicon Nanostructures and Photoluminescence
- Radio Astronomy Observations and Technology
- Quantum, superfluid, helium dynamics
Chinese Academy of Medical Sciences & Peking Union Medical College
2025
China Medical University
2025
First Hospital of China Medical University
2025
Lanzhou University
2019-2024
Shandong Academy of Sciences
2024
Qilu University of Technology
2024
Institute of Theoretical Physics
2023-2024
Chinese Academy of Sciences
2023-2024
University of Chinese Academy of Sciences
2023-2024
Shanghai University of Engineering Science
2022
We study the power spectrum of comoving curvature perturbation $\cal R$ in model that glues two linear potentials different slopes, originally proposed by Starobinsky. find enhanced reaches its maximum at wavenumber which is $\pi$ times junction scale. The peak $\sim2.61$ larger than ultraviolet plateau. also show near-peak behavior can be well approximated a constant-roll model, once we define effective ultra-slow-roll $e$-folding number appropriately considering contribution from...
Abstract We thoroughly study the induced gravitational wave interpretation of possible background reported by PTA collaborations, considering unknown equation state w early universe. perform a Bayesian analysis NANOGrav data using publicly available PTArcade code together with SIGWfast for numerical integration spectrum. focus on two cases: monochromatic and log-normal primordial spectrum fluctuations. For spectrum, we show that, while results are not very sensitive to when GW peak is close...
Abstract Magnetic skyrmion-based spin transfer nano-oscillators (STNOs) have been proposed as microwave signal generators and attracted enormous interest recently. However, the oscillation frequency of STNOs is about 2 GHz, which not so high for practical applications. In this paper, we create an annular groove in surface free layer put skyrmions groove. Due to potential groove, are confined moving when driven by spin-polarized currents. Through micromagnetic simulations, it found that...
Skyrmion bags are found in liquid crystals and predicted to exist ferromagnetic films. They expected become the information carriers of new generation racetrack memory due their high-degree freedom topological charge number. Here, we numerically theoretically investigate dynamics skyrmion driven by spin–orbit torque an infinite film a nanostrip with finite length. It is that constant velocity bag depends on its number, while case motion nanostrips moving along boundary, first approximation...
High-frequency primordial gravitational waves (PGWs) with wave numbers larger than the Hubble parameter at end of inflation are originated from ultraviolet (UV) modes, which never stretched out horizon. Such a UV tail PGW energy spectrum has spurious logarithmic divergence. We study origin such divergence, and find that it comes instantaneous inflation-to-postinflation transition, can be removed by considering finite duration. For first time, we obtain semianalytical expression for spectrum....
Magnetic skyrmionium is a novel magnetization configuration with zero skyrmion number, which composed by two skyrmions opposite number. Here, we study the dynamics of under an anisotropy gradient. We find that can be efficiently driven gradient moving straightly along direction The Hall angle for close to much smaller than skyrmion. while speed larger. also demonstrate motion depends on damping cofficient, and stabilization in modulated narrowing width nanowire. Our work shows efficient...
ASO-S is a mission proposed for the 25th solar maximum by Chinese community. The scientific objectives are to study relationships among magnetic field, flares, and coronal mass ejections (CMEs). consists of three payloads: Full-disk Magnetograph (FMG), Lyman-alpha Solar Telescope (LST), Hard X-ray Imager (HXI), measure observe CMEs respectively. now under phase-B studies. This paper makes brief introduction mission.
We explore the FeRh magnetic phase transition (MPT) and domain (MPD) with introduction of surface acoustic waves (SAWs). The effects SAW pulses different pulse widths powers on resistance-temperature loops are investigated, revealing that can reduce thermal hysteresis. Meanwhile, SAW-induced comb-like antiferromagnetic (AFM) domains observed. By changing width frequency, we further realize a writing-erasing process AFM in mixed-phase regime cooling branch. Resistance measurements also...
Twisted skyrmions, whose helicity angles are different from those of Bloch and Néel have recently been demonstrated in experiments. In this work, we first discuss the origin topological properties twisted skyrmions. Following that, investigate current-induced motion skyrmions by using micromagnetic simulations. It is found that skyrmion Hall angle driven spin effect (SHE) varies continuously with helicity, which means depends significantly upon addition to dissipative force tensor Gilbert...
The spin torque nano-oscillators (STNOs) have garnered significant interest as a potential nanosized microwave signal generator. However, the core of magnetic radial vortex may be annihilated at edge with large polarized current density, which leads to unstable STNOs. In this work, we propose new STNOs based on by overcoming annihilation edge, was realized adding high crystal anisotropy materials boundary nanodisk. It is found that oscillation frequency reaches up 2.8 GHz through circular...
Skyrmions in synthetic antiferromagnets (SAFs) are famous for being immune to the skyrmion Hall effect and hold advantages of significantly higher speed motion smaller size than ferromagnetic systems. Therefore, skyrmions SAFs promising spintronic devices. Here, we investigated formation in-plane-current-driven bilayer absence Dzyaloshinskii–Moriya interaction by using micromagnetic simulations. Then, studied spacing variation between consecutive skyrmionic bits on antiferromagnetic coupled...
The 16 low resolution spectrographs (LRS) have been successfully commissioned for the LAMOST. LRS design employs a dual-beamed and bench-mounted, with large-beamed, fast Schmidt cameras Volume Phase Holographic (VPH) transmission gratings. wavelength range is 370-900nm, at resolutions of R=1000and R=10000. Each spectrograph fed by 250 fibers 320 micron in diameter (corresponding 3.3 arcsec), composed one F/4 collimator, dichroic beam-splitter, four VPH gratings, articulating that are...
Abstract A biskyrmion, which consist of two stable Bloch skyrmions with opposite magnetic helicities has been observed in several centrosymmetric ferromagnets such as layered perovskite manganites and MnNiGa. Here, the spin excitation modes biskyrmion a confined nanodot were investigated by using micromagnetic simulations. An oscillation mode at lower frequency mixed breathing rotation higher frequencies are observed. In addition, for exhibit remarkable dependence on change magnetization...
High-frequency primordial gravitational waves (PGWs) with wave numbers larger than the Hubble parameter at end of inflation are originated from ultraviolet (UV) modes, which never stretched out horizon. Such a UV tail PGW energy spectrum has spurious logarithmic divergence. We study origin such divergence, and find that it comes instantaneous inflation-to-post-inflation transition, can be removed by considering finite duration. For first time, we obtain semi-analytical expression for...
Primordial Black Holes (PBHs) can form from gravitational collapse of large overdensities in the early Universe, giving rise to rich phenomena astrophysics and cosmology. We develop a novel, general, accurate method based on theory density contrast peaks calculate abundance PBHs for broad power spectrum curvature perturbations with Gaussian statistics. By introducing window function account relevant perturbation scales different masses, as well filter circumventing overproduction small PBHs,...
Abstract Spin pumping is a widely recognized method to generate the spin current in spintronics, which can be found varieties of magnetic materials and acknowledged as fundamentally dynamic process equivalent spin-transfer torque. In this work, we theoretically verified oscillating mixed by AC DC components pumped from microwave-motivated breathing skyrmion. The within relatively low-frequency microwave compared with in-plane ferromagnetic resonance (FMR). Although amplitude density for...