Nara Lee
Yonsei University · 材料科学
研究室紹介
Professor Nara Lee's research lab specializes in strongly correlated quantum materials, with a focus on multiferroics, antiferromagnetic spintronics, and magnetoelectric materials. The lab investigates novel electronic and magnetic states, particularly in iridates and rare-earth perovskites, to explore intrinsic coupling between spin, charge, and lattice degrees of freedom. Key research directions include the manipulation of isospin and magnetic anisotropy for spintronic applications, nonlinear magnetoelectric effects, and the development of functional oxides with tailored multifunctional properties. The lab also engages in the synthesis and stabilization of advanced nanomaterials, such as functional nZVI, for environmental and energy applications.
Research Overview
Research Output Trend
Figures are computed from collected data and may differ slightly.
Selected Papers
15Abstract The novel electronic state of the canted antiferromagnetic (AFM) insulator strontium iridate (Sr 2 IrO 4 ) is well described by the spin–orbit‐entangled isospin J eff = 1/2, but the role of isospin in transport phenomena remains poorly understood. In this study, antiferromagnet‐based spintronic functionality is demonstrated by combining the unique characteristics of the isospin state in Sr 2 IrO 4 . Based on magnetic and transport measurements, a large and highly anisotropic magnetoresi
Abstract In rare-earth orthoferrites, strongly correlated order parameters have been thoroughly investigated, which aims to find multiple functionalities such as multiferroic or magnetoelectric properties. We have discovered highly anisotropic and nonlinear magnetodielectric effects from detailed measurements of magnetoelectric properties in single-crystalline orthoferrite, ErFeO 3 . Isothermal dielectric constant varies in shapes and signs depending on the relative orientations between the exte
We report on the growth of multiferroic Yb2CoMnO6 and Lu2CoMnO6 single crystals which were synthesized by the flux method with Bi2O3. Yb2CoMnO6 and Lu2CoMnO6 crystallize in a double-perovskite structure with a monoclinic P21/n space group. Bulk magnetization measurements of both specimens revealed strong magnetic anisotropy and metamagnetic transitions. We observed a dielectric anomaly perpendicular to the c axis. The strongly coupled magnetic and dielectric states resulted in the variation of b
Abstract Strongly correlated materials with multiple order parameters provide unique insights into the fundamental interactions in condensed matter systems and present opportunities for innovative technological applications. A class of antiferromagnetic honeycomb lattices compounds, A 4 B 2 O 9 (A = Co, Fe, Mn; B = Nb, Ta), have been explored owing to the occurrence of linear magnetoelectricity. From our investigation of magnetoelectricity on single crystalline Co 4 Ta 2 O 9 , we discovered stro
Abstract Magnetic anisotropy is crucial in examining suitable materials for magnetic functionalities because it affects their magnetic characteristics. In this study, disordered-perovskite RCr 0.5 Fe 0.5 O 3 (R = Gd, Er) single crystals were synthesized and the influence of magnetic anisotropy and additional ordering of rare-earth moments on cryogenic magnetocaloric properties was investigated. Both GdCr 0.5 Fe 0.5 O 3 (GCFO) and ErCr 0.5 Fe 0.5 O 3 (ECFO) crystallize in an orthorhombic Pbnm str
PURPOSE: Regulatory T (Treg) cells are key modulators in the immune system. Recent studies have shown that atopic dermatitis (AD) patients have higher numbers of Treg cells; however, little is known about the specific phenotype and function of Treg cells in AD. MATERIALS AND METHODS: To identify differentially expressed proteins in peripheral induced Treg cells in AD and naturally derived Treg cells in normal controls, CD4⁺CD25⁺ Treg cells were isolated from thymus tissue of normal mice and the
This study aimed to synthesize dispersed and reactive nanoscale zero-valent iron (nZVI) with poly(1-vinylpyrrolidone-co-vinyl acetate) (PVP/VA), nontoxic and biodegradable stabilizer. The nZVI used for the experiments was prepared by reduction of ferric solution in the presence of PVP/VA with specific weight ratios to iron contents. Colloidal stability was investigated based on the rate of sedimentation, hydrodynamic radius and zeta potential measurement. The characteristic time, which demonstra
Abstract The influence of magnetocrystalline anisotropy in antiferromagnets is evident in a spin flip or flop transition. Contrary to spin flops, a spin-flip transition has been scarcely presented due to its specific condition of relatively strong magnetocrystalline anisotropy and the role of spin-flips on anisotropic phenomena has not been investigated in detail. In this study, we present antiferromagnet-based functional properties on an itinerant Ising antiferromagnet Ca 0.9 Sr 0.1 Co 2 As 2 .
본 연구에서는 국소적 부위에 균일한 자극이 가능한 Pulsed Magnetic Fields(PMFs) 시스템을 개발하였으며, 지연성 근육통증에 대한 본 시스템의 효과를 확인하고자 하였다. 지연성 근육통을 유발시키기 위해 비주동팔에서 무게 5Kg의 아령으로 80회의 등장성운동을 실시하였다. 피험자를 세 군(PMFs군, TEAS군, 무자극군)으로 분류한 뒤 상완 이두박근에 위치한 청영혈(HT2)에 자극하였다. 지연성 근육통의 회복여부를 판별하기 위하여, 상완이두박근에서의 |좌/우 온도차|를 DITI를 이용하여 비교⋅분석하였다. 그 결과, 운동 후의 |좌/우 온도차|는 무자극군=2.00±1.16℃, TEAS군=1.73±0.52℃, PMFs군=1.48±0.51℃로 나타났으며, 첫 번째 자극 후에는 무자극군=1.37±0.71℃, TEAS군=1.08±0.43℃, PMFs군=1.23±0.15℃로 나타났다. 24시간이 지난 후에 자기장 군이 가장 먼저 0.05±0.06℃의 좌/우 온도차이로 정상
It has recently been reported that the exchange bias (EB) phenomenon in double‐perovskite Y 2 CoMnO 6 ceramic arises from additional antiferromagnetic (AFM) clusters formed by the anti‐sites of ionic disorders in the dominant ferromagnetic (FM) phase. To extensively examine the role of ionic orders and versatile magnetic interactions, we measure the magnetic properties of Y 2 Co 2 − x Mn x O 6 ( x = 1.0–1.9) compounds with different relative ratios of the magnetic ions. Upon increasing the ratio
Objectives : The aim of this study is to propose the W area of pulse (AW) as a new index which can confirm the arteriosclerosis by analyzing parameters of 5-level pressure pulse waveform measurement system for normotensive group according to aging. Methods : We measured radial pulse waveforms of normotensive group (20 to 60 years old) using 3-dimensional pulse imaging analyser (DMP-3000, DAEYOMEDI Co., Korea). And then we analyzed various parameters for sclerosis of the arteries such as Height (
The revision of the Korea Organ Transplantation Act (KOTA) in 2018 included hand/arm among the organs that can be transplanted. The first hand transplantation since the revision of KOTA took place in January 2021. A 62-year-old male patient experienced hand amputation on July 13, 2018, by a catapult injury. The patient first visited our institute 3 months after the injury. After serial interviews and an overall evaluation, the patient was registered on the hand transplantation waiting list in Ja
Abstract Spin-flip transition can occur in antiferromagnets with strong magnetocrystalline anisotropy, inducing a significant modification of the anisotropic magnetic properties through phase conversion. In contrast to ferromagnets, antiferromagnets have not been thoroughly examined in terms of their anisotropic characteristics. We investigated the magnetic-field and angle-dependent magnetic properties of Ising-type antiferromagnetic Ca 0.9 Sr 0.1 Co 2 As 2 using magnetic torque measurements. An