logo

korean english

게시판

Home > 게시판 > 세미나

일시: 8월 5일(금) 오전 10:30 ~ 12:00

장소: 31동 2층 물리학과 라운지세미나실

연사: 김  세  권 박사님 (UCLA)


Title: Phase Slips in Superfluid Spin Transport in Magnetic Wires


○ Abstract:

In this talk, we will discuss two types of mechanisms responsible for intrinsic resistance in superfluid spin transport in easy-plane magnetic wires: thermally-activated and quantum phase slips. First, we theoretically study thermally-activated phase slips within the stochastic Landau-Lifshitz-Gilbert phenomenology, which runs parallel to the Langer-Ambegaokar-McCumber-Halperin theory for thermal resistances in superconducting wires [1]. To that end, we start by obtaining the exact solutions for free-energy minima and saddle points. We provide an analytical expression for the phase-slip rate in the zero spin-current limit, which involves detailed analysis of spin fluctuations at extrema of the free energy. 


Secondly, we theoretically investigate effects of quantum fluctuations on superfluid spin transport through easy-plane quantum antiferromagnetic spin chains in the large-spin limit [2]. Quantum fluctuations result in the decaying spin supercurrent by unwinding the magnetic order parameter within the easy plane, which is referred to as phase slips. We show that the topological term in the nonlinear sigma model for the spin chains qualitatively differentiates decaying rate of the spin supercurrent between integer and half-odd-integer spin chains. We propose an experimental setup for a magnetoelectric circuit, in which both phase slips can be inferred by measuring nonlocal magnetoresistance.


[1] S. K. Kim, S. Takei, and Y. Tserkovnyak, Phys. Rev. B \textbf{93}, 020402(R) (2016)

[2] S. K. Kim and Y. Tserkovnyak, Phys. Rev. Lett. \textbf{116}, 127201 (2016)



번호 제목 날짜 조회 수
공지 <12/8(Thu.) 11:00am>노벨상 소개 강연 - 2016년 노벨 물리학상: 위상 응집 물리의 탄생 2016.11.28 1079691
587 <7/21(월)> The rapid neutron capture nucleosynthesis: A hot topic in the Nuclear Astrophysics study 2014.07.15 121467
586 <5/15>Black Hole Entropy Function in (Anti-)de Sitter Space-Time 2008.05.09 121217
585 <7/20(Thu.)14:00>Engineering and probing topological properties of Dirac semimetal films by asymmetric charge transfer 2017.07.18 120913
584 <12/4> The "Physics" of Climate Change 2009.12.02 119219
583 <4/27> Organic-based Magnet and Organic-based spintronics : New science and Technologies 2010.04.22 118527
582 <Oct.15(Thu) 16:30> Single-Molecule Approach to Homology Search & Strand Exchange in Homologous Recombination 2015.10.12 117742
581 <8/5>Brane superpotential via local Calabi-Yau spaces 2009.08.03 117678
580 <5/14> Search for exotic materials: strongly correlated electron system 2010.05.10 116939
579 <6/18> Multiferroics: Magnetism-driven Ferroelectricity 2009.05.27 116109
578 <Sep. 29(Wed.)> Longitudinal Spin Seebeck effect in Pt/YIG structure with monolayer WSe2 and MoS2 interlayer 2021.09.16 115870
577 <10/15> Electric control of magnetic nanostructures via spin torque 2010.10.08 115838
576 <8/17> AdS Black Hole Solutions in Extended New Massive Gravity 2010.08.16 115789
575 <May 17(Wed.) 4:30 PM>Printed Electronics 2017.05.10 115680
574 <4/13> Introduction to Quantum Information Processing 2007.04.11 115470
573 <Nov. 8(Wed.) 4:30 PM> 연성물질 기반 위상학적 결함구조의 상전이와 응 2017.11.01 115418
572 <7/24(Mon.)11:00>Antenna Arrays for Astroparticle Physics: Radio Detection of High-Energy Cosmic Rays 2017.07.19 115245
571 <6/11(Mon.)3:30pm> Spontaneous Leptogenesis in Continuum-Clockwork Axion Models 2018.06.08 115047
570 <7/28> NQR/NMR study on a single crystal of LiFeAs 2010.07.20 114593
569 <2/16>Development of Micromegas detectors for neutron physics 2010.02.01 114144
568 <3/26> Shedding infrared light on high-Tc superconductors 2014.03.19 113999