visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2022-05-13 14:30 
일시 May. 13 (Fri.), 02:30 PM 
장소 Zoom webinar 
연사 Dr. Kun-Rok Jeon(Department of Physics, Chung-Ang University) 

SRC Seminar

 

 

Topological Superconducting Spintronics Towards Zero-Power Computing Technologies

 

Dr. Kun-Rok Jeon

Department of Physics, Chung-Ang University

 

May. 13 (Fri.), 02:30 PM

https://kaist.zoom.us/j/88323922428
회의 ID: 883 2392 2428

암호: 839974

Abstract:

Semiconductor (SC) spintronics [1-4] aims to integrate memory and logic functions into a single device. Ferromagnetic tunnel contacts have emerged as a robust and technically viable method to inject spin current into a SC up to room temperature, and to detect it [3-7]. Intriguingly, it has been established that the spin current in ferromagnetic tunnel contacts can be created by thermal means (driven by a heat flow), namely Seebeck spin tunneling [8]. So far, the creation of thermal spin current relies on the spin-dependent energy dispersion of electronic states around the Fermi energy (EF), which determines thermoelectric properties. In the first part of my talk, I will describe a conceptually new approach to tailor the thermal spin current in ferromagnetic tunnel contacts to SCs exploiting spin-dependent thermoelectric properties away from EF through the application of a bias voltage across the tunnel contact [9,10].

Combining superconductivity with spintronics brings in a variety of notable phenomena which do not exist in the normal state, for instance quantum coherence, superconducting exchange coupling and spin-polarized triplet supercurrents [11,12]. This nascent field of superconducting spintronics promises to realize zero-energy-dissipation spin transfer and magnetization switching. Recent equilibrium (zero-bias) studies of the Josephson effect in S/FM/S (FM: ferromagnet; S: Superconductor) junctions and the critical temperature Tc modulation in FM/S/FM and S/FM/FM' superconducting spin valves have demonstrated that engineered magnetically-inhomogeneous S/FM interfaces can generate long-range triplet pairing states which explicitly carry spin [11,12]. However, direct measurement of triplet spin transport through a singlet S has not so far been achieved. In the second part, I will describe an essentially different approach, namely, a time-dependent ferromagnetic magnetization [ferromagnetic resonance (FMR)] can drive spin-polarized transport in a singlet S via spin-triplet states induced by spin-orbit coupling [13,14].

If time permits, I will briefly outline outstanding technical issues for the realization of energy-efficient (or even dissipation-less) spintronic technologies and present my research direction of how to address these issues via topology physics [15,16].

Reference: [1] Rev. Mod. Phys. 80, 1517 (2008), [2] Rev. Mod. Phys. 76, 323 (2004), [3] Nat. Mater. 11, 400 (2012), [4] Semicond. Sci. Technol. 27, 083001 (2012), [5] Nature 462, 491 (2009), [6] Appl. Phys. Express 4, 023003 (2011), [7] Phys. Rev. Appl. 2, 034005 (2014), [8] Nature 475, 82 (2011), [9] Nat. Mater. 13, 360 (2014), [10] Phys. Rev. B 91, 155305 (2015), [11] Nat. Phys. 11, 307 (2015), [12] Rep. Prog. Phys. 78, 104501 (2015), [13] Nat. Mater. 17, 499 (2018), [14] Phys. Rev. X 10, 031020 (2020), [15] Nat. Mater. 20, 1358 (2021), [16] Under review in Nat. Nanotech. (2022).

 

Contact: SunYoung Choi, (sun.0@kaist.ac.kr)

Center for Quantum Coherence in Condensed Matter, KAIST

번호 날짜 장소 제목
공지 2022-10-24 16:00  E6 #1501(공동강의실)  Physics Colloquim(Fall 2022)
공지 2022-09-21 10:30  E6-1 #1501  [Update 세미나 영상] Distinguished Lecture 'The Magic of Moiré Quantum Matter' Prof. Pablo Jarillo-Herrero(Department of Physics, MIT)
공지 2022-10-28 11:00  E6-2 #1323  [Update 세미나영상] (응집물리 세미나) Machine-Learning-Guided Prediction models and Materials discovery for high Tc cuprates
공지 2022-10-07 11:00  E6-2 #1323  [Update 세미나 영상] (응집물리 세미나) Competing orders in a vanadium-based kagome metal monolayer
공지 2022-09-23 11:00  E6-2 #1323  [Update 세미나 영상] (응집물리 세미나) Steady Floquet-Andreev states in graphene Josephson junctions
공지 2022-09-22 11:00  E6-1 #1323  2022 가을학기 응집물리 및 광학 세미나 전체 일정
133 2017-02-01 14:00  #1323(E6-2. 1st fl.)  Quantum electron optics using flying electrons
132 2015-11-23 13:30  E6-2, #1323  What's Beyond the Standard Model? Lessons from Run I and what might come in Run II
131 2016-07-08 11:00  #1323(E6-2. 1st fl.)  Isostatic magnetism
130 2016-05-19 15:00  May 19, 2016 (Thur.) 3PM,  The CERN Resonant WISP Search: Development, Results and Lesson-Learned
129 2015-10-15 10:00  E6-2, 5th fl. #5318  Development of Large-Bore, High Field Magnets at the NHMFL
128 2017-03-24 14:30  #1323 (1st fl. E6-2).  Topological Dynamics
127 2018-10-26 16:00  #1323, E6-2  Coexisting triple-point and nodal-line topological magnons and thermal Hall effect in pyrochlore iridates file
126 2015-07-16 16:00  E6-2, 1318  Next-generation ultrafast laser technology for nonlinear optics and strong-field physics
125 2022-08-18 10:00  E6-1 #1323  Disorder-driven phase transition in the second-order non-Hermitian skin effect
124 2018-11-01 16:00  #1323, E6-2  Direct holography from a single snapshot file
123 2016-03-11 13:30  E6-2. 1st fl. #1501  Topological phases of matter in nonequilibrium: Topology of the Wannier-Stark ladder
122 2015-12-11 13:30  E6-2, #1323  Quantum spin liquid in the 1/3 depleted triangular lattice Ba3(Ru1-xIrx)Ti2O9
121 2021-07-29 14:00  Online seminar  Gravitationally Induced Dark Sector and Inflationary Dynamics file
» 2022-05-13 14:30  Zoom webinar  Topological Superconducting Spintronics Towards Zero-Power Computing Technologies file
119 2016-12-09 16:00  #1323(E6-2. 1st fl.  Shift Charge and Spin Photocurrents in Dirac Surface States of Topological Insulator
118 2018-05-11 14:30  E6-2. 1st fl. #1323  Disordered Floquet topological insulators file
117 2016-05-31 16:00  #1323(E6-2, 1st fl.)  Understanding 3D tokamak physics towards advanced control of toroidal plasma
116 2016-04-01 14:30  E6-2. 1st fl. #1501  Interference of single charged particles without a loop and dynamic nonlocality
115 2016-11-11 13:30  #1323(E6-2. 1st fl.)  Bandgap Engineering of Black Phosphorus
114 2021-06-11 16:00  Online seminar  Pseudogap in surface-doped black phosphorus file