https://scholar.korea.ac.kr/handle/2021.sw.korea/698 Tue, 07 Apr 2026 21:04:32 GMT 2026-04-07T21:04:32Z https://scholar.korea.ac.kr/handle/2021.sw.korea/267327 Title: The control of magnetization reversal by tuning the interlayer exchange interaction in magnetic multilayers Authors: Yu, Seunghoon; Park, Jinhyeok; Jo, Yonghwan; Kim, Woojong; Kim, Hyeonsu; Choi, Won-Young; Kim, Mingu; Han, Dong-Soo; Jung, Myung-Hwa; Rhie, Kungwon; Lee, Kyujoon Abstract: The interest of noncollinear spin structures in magnetic multilayers has recently gained a lot of interest in spintronics due to the observation of unique phenomena in these systems. In magnetic multilayers coupled by the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction the study of noncollinear interactions has gained interest. In this paper, we study the magnetization reversal of two magnetic layers with different magnetic anisotropy directions coupled by the RKKY interaction. We have chosen Pt/Co/Ru/Co40Fe40B20 structures where the Pt/Co show perpendicular-magnetic anisotropy and CoFeB show an in-plane magnetic anisotropy. Wed, 01 Jan 2025 00:00:00 GMT https://scholar.korea.ac.kr/handle/2021.sw.korea/267327 2025-01-01T00:00:00Z https://scholar.korea.ac.kr/handle/2021.sw.korea/218597 Title: Advancements in halide perovskite photonics Authors: Yu, Weili; Lee, Kwang jin; Li, Yixuan; Huang, Ziyuan; Zhou, Rongxue; Chen, Ao; Guo, Chunlei Abstract: Halide perovskites have emerged as a new class of materials for photoelectric conversion, attracting an ever-increasing level of attention within the scientific community. These materials are characterized by expansive compositional choices, ease of synthesis, an impressively high light absorption coefficient, and extended carrier recombination lifetimes. These attributes make halide perovskites an ideal candidate for future optoelectronic and photonic applications, including solar energy conversion, photodetection, electroluminescence, coherent light generation, and nonlinear optical interactions. In this review, we first introduce fundamental concepts of perovskites and categorize perovskite photonic devices by the nature of their fundamental mechanisms, i.e., photon-to-electron conversion devices, electron-to-photon conversion devices, and photon-to-photon devices. We then review the significant progress in each type of perovskite device, focusing on working principles and device performances. Finally, future challenges and outlook in halide perovskite photonics will be provided. (c) 2024 Optica Publishing Group. All rights, including for text and data mining (TDM), Artificial Intelligence (AI) training, and similar technologies, are reserved. Tue, 31 Dec 2024 00:00:00 GMT https://scholar.korea.ac.kr/handle/2021.sw.korea/218597 2024-12-31T00:00:00Z https://scholar.korea.ac.kr/handle/2021.sw.korea/198126 Title: Frequency dependence of nanorod self-alignment using microfluidic methods Authors: Shin, Hosan; Hong, Lia; Park, Woosung; Shin, Jeeyoung; Park, Jae Byung Abstract: Dielectrophoresis is a potential candidate for aligning nanorods on electrodes, in which the interplay between electric fields and microfluidics is critically associated with its yield. Despite much of previous work on dielectrophoresis, the impact of frequency modulation on dielectrophoresis-driven nanorod self-assembly is insufficiently understood. In this work, we systematically explore the frequency dependence of the self-alignment of silicon nanorod using a microfluidic channel. We vary the frequency from 1kHz to 1000 kHz and analyze the resulting alignments in conjunction with numerical analysis. Our experiment reveals an optimal alignment yield at approximately 100 kHz, followed by a decrease in alignment efficiency. The nanorod self-alignments are influenced by multiple consequences, including the trapping effect, induced electrical double layer, electrohydrodynamic flow, and particle detachment. This study provides insights into the impact of frequency modulation of electric fields on the alignment of silicon nanorods using dielectrophoresis, broadening its use in various future nanotechnology applications. Mon, 22 Jul 2024 00:00:00 GMT https://scholar.korea.ac.kr/handle/2021.sw.korea/198126 2024-07-22T00:00:00Z https://scholar.korea.ac.kr/handle/2021.sw.korea/198729 Title: Fractonic quantum quench in dipole-constrained bosons Authors: Oh, Yun-Tak; Han, Jung Hoon; Lee, Hyun-Yong Abstract: "We investigate the quench dynamics in the dipolar Bose-Hubbard model (DBHM) in one dimension. The boson hopping is constrained by dipole conservation and shows fractonic dynamics. The ground states at large Hubbard interaction U are Mott insulators at integer filling and a period-2 charge density wave (CDW) at half-integer filling. We focus on Mott-to-Mott and CDW-to-CDW quenches and find that dipole correlation spreading shows the light-cone behavior with the Lieb-Robinson (LR) velocity proportional to the dipole kinetic energy J and the square of the density in the case of Mott quench at integer filling. An effective model for postquench dynamics is constructed under the dilute-dipole approximation and fits the numerical results well. For the CDW quench, we observe a much reduced LR velocity of order J2/U and additional periodic features in the time direction. The emergence of a CDW ground state and the reduced LR velocity at half-integer filling can both be understood by careful application of the second-order perturbation theory. The oscillatory behavior arises from quantum scars in the quadrupole sector of the spectrum and is captured by a PXP-like model that we derive by projecting the DBHM to the quadrupolar sector of the Hilbert space. © 2024 authors. Published by the American Physical Society. Mon, 01 Apr 2024 00:00:00 GMT https://scholar.korea.ac.kr/handle/2021.sw.korea/198729 2024-04-01T00:00:00Z