A5101447965- Physics of Superconductivity and Magnetism
- Quantum and electron transport phenomena
- Rare-earth and actinide compounds
- Topological Materials and Phenomena
- Advancements in Semiconductor Devices and Circuit Design
- Magnetic and transport properties of perovskites and related materials
- Iron-based superconductors research
- Advanced Condensed Matter Physics
- Multiferroics and related materials
- Magnetic properties of thin films
- Semiconductor Quantum Structures and Devices
- Superconductivity in MgB2 and Alloys
- Advanced Chemical Physics Studies
- Lightning and Electromagnetic Phenomena
- Quantum Computing Algorithms and Architecture
- Superconducting Materials and Applications
- Terahertz technology and applications
- Radio Frequency Integrated Circuit Design
- Graphene research and applications
- Heusler alloys: electronic and magnetic properties
- Smart Grid and Power Systems
- Advanced Decision-Making Techniques
- Ferroelectric and Negative Capacitance Devices
Kyungpook National University
2019-2024
Time reversal symmetry (TRS) breaking often generates exotic quantum phases in condensed matter. In superconductors, TRS by an external magnetic field not only suppresses superconductivity but also leads to a novel state called the gapless superconducting state. Here we show that magneto-terahertz spectroscopy provides us with rare opportunity access and explore of Nb thin films. We present complete functional form order parameter for arbitrary field, which fully self-consistent theory is,...
Abstract The anomalous Hall conductivity (AHC) in magnetic materials, resulting from inverted band topology, has emerged as a key adjustable function spin‐torque devices and advanced sensors. Among systems with near‐half‐metallicity broken time‐reversal symmetry, cobalt disulfide (CoS 2 ) proven to be material capable of significantly enhancing its AHC. In this study, the AHC CoS is empirically assessed by manipulating chemical potential through Fe‐ (hole) Ni‐ (electron) doping. primary...
Finding d-electron heavy fermion (HF) states has been an important topic as the diversity in materials can lead to many exotic Kondo effect-related phenomena or new of matter such correlation-driven topological insulator cooperation between long-range magnetism and lattice behavior. Yet, obtaining direct spectroscopic evidence for a HF system elusive date. Here, we report observation behavior antiferromagnetic metal, FeTe, via angle-resolved photoemission spectroscopy (ARPES) transport...
Cryogenic RF transistors and routing circuits operating with extremely low power are essential as control/readout electronics for future large-scale quantum computing (QC) systems. In this work, we demonstrate 3D stackable InGaAs HEMT-based cryogenic integrated Nb superconductors ultra-low operation. As a result, achieve record high unity current gain cutoff frequency $(f_{T})$ of 601 GHz $(f_{MAX})$ 593 at 4 K the smallest dissipation among ever reported transistors. Furthermore, using...
Quantum computers now encounter the significant challenge of scalability, similar to issue that classical computing faced previously. Recent results in high-fidelity spin qubits manufactured with a Si CMOS technology, along demonstrations cryogenic CMOS-based control/readout electronics can be integrated into same chip or die, opens up an opportunity break out challenges qubit size, I/O, and integrability. However, power consumption cannot support thousands millions qubits. Here, we show...
Abstract The study of the high critical temperature ( T c ) hydrogen compounds under pressure has resulted in a considerable focus on Bardeen–Cooper–Schrieffer superconductors. Nb highest among elemental metals at ambient pressure, so reviewing films again is worthwhile. In this study, we investigated factors that determine by strain introduction and carrier doping. We deposited various thicknesses onto Si substrates evaluated variation with thickness. In-plane compressive (110) plane due to...
The key of spintronic devices using the spin-transfer torque phenomenon is effective reduction switching current density by lowering damping constant and saturation magnetization while retaining strong perpendicular magnetic anisotropy. To reduce magnetization, particular conditions such as specific substitutions or buffer layers are required. Herein, we demonstrate highly reduced in tetragonal D022 Mn3–xGa thin films prepared rf magnetron sputtering, where epitaxial growth examined on...
Magnetic anisotropy in strontium iridate (Sr2IrO4) is essential because of its strong spin-orbit coupling and crystal field effect. In this paper, we present a detailed mapping the out-of-plane (OOP) magnetic Sr2IrO4for different sample orientations using torque magnetometry measurements low-magnetic-field region before isospins are completely ordered. Dominant in-plane was identified at low fields, confirming thebaxis as an easy magnetization axis. Based on fitting analysis uniaxial...
The strong coupling between magnetic, structural, and electronic degrees of freedom is a prominent feature Fe-based superconductors. However, the relationship vortex dynamics remains unclear. In this paper, we measure pinning energy ${U}_{0}/{k}_{\mathrm{B}}$ within thermally activated flux-flow regime with respect to pressure-induced phases in FeSe single crystal. We show that dependence on pressure, measured at magnetic field higher than crossover ${H}_{\mathrm{cr}}$, follows trend like...
Recent dramatic climate change requires stronger responses since damages from lightning are increasing although countermeasures for the in operation of power system have long been a challenge. In this paper, effect surge on distribution and importance protection examined first. Then, voltage limit, method pillar transformer surge, main causes failure life span reduction transformer, devices its investigated. The is analyzed it was identified that difference lead wire length arrester makes...
Abstract Time reversal symmetry (TRS) breaking often generates exotic quantum phases in condensed matter. In superconductors, TRS by an external magnetic field not only suppresses superconductivity but also leads to a novel state called the gapless superconducting state. Here we show that magneto-terahertz spectroscopy provides us with rare opportunity access and explore of Nb thin films. We present complete functional form order parameter for arbitrary field, which fully self-consistent...
Abstract Magnetic anisotropy in strontium iridate (Sr 2 IrO 4 ) is essential because of its strong spin-orbit coupling and crystal field effect. In this study, we investigated the detailed mapping out-of-plane (OOP) magnetic Sr for different sample orientations using torque magnetometry measurements low-magnetic-field region before isospins are fully ordered. Dominant in-plane was identified at low fields, confirming b axis as an easy magnetization axis. Based on fitting analysis uniaxial...