|일시||May. 13 (Fri.), 02:30 PM|
|연사||Dr. Kun-Rok Jeon(Department of Physics, Chung-Ang University)|
“Topological Superconducting Spintronics Towards Zero-Power Computing Technologies”
Dr. Kun-Rok Jeon
Department of Physics, Chung-Ang University
May. 13 (Fri.), 02:30 PM
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 . 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:  Rev. Mod. Phys. 80, 1517 (2008),  Rev. Mod. Phys. 76, 323 (2004),  Nat. Mater. 11, 400 (2012),  Semicond. Sci. Technol. 27, 083001 (2012),  Nature 462, 491 (2009),  Appl. Phys. Express 4, 023003 (2011),  Phys. Rev. Appl. 2, 034005 (2014),  Nature 475, 82 (2011),  Nat. Mater. 13, 360 (2014),  Phys. Rev. B 91, 155305 (2015),  Nat. Phys. 11, 307 (2015),  Rep. Prog. Phys. 78, 104501 (2015),  Nat. Mater. 17, 499 (2018),  Phys. Rev. X 10, 031020 (2020),  Nat. Mater. 20, 1358 (2021),  Under review in Nat. Nanotech. (2022).
Contact: SunYoung Choi, (email@example.com)
Center for Quantum Coherence in Condensed Matter, KAIST
|42||July 27, 2018 at 15:00||Room 5318, KAIST Natural Sciences Lecture Hall(E6).||Dr. Hyejung Kim(Technische University Dresden)||Muon g-2 in the 2HDM and MSSM: comprehensive numerical analysis and absolute maxima|
|41||July 13, 2018 at 14:00||Room 5318, KAIST Natural Sciences Lecture Hall(E6).||Prof. Ian Lewis (The University of Kansas, Department of Physics & Astronomy)||Loop Induced Single Top Partner Production and Decay at the LHC|
|40||2019/09/18 - 12/5||Seminar Room #1323||Prof. David Schuster and etc.||Fall 2019: Physics Seminar Serises|
|39||Nov. 1 (Tue.) 2:30 pm||Seminar Room #1323(E6-2)||Prof. Youngjoon Kwon, Yonsei Univ.||Search for dark sector particles in the B-factory experiments|
|38||Jun. 14 (Tue) 4PM||Seminar Room (#2502, 2nd fl.)||Young-Sik Ra, Université Pierre et Marie Curie||Photonic quantum network based on multimode squeezed vacuums and single-photon subtraction|
|37||July 2. 2018 (Monday) 3:00 PM||Seminar Room (C303), Creation Hall (3F), KAIST Munji Campus||Dr. Peter Winter (Argonne National Laboratory)||High Precision Magnetic Field Measurement for the Muon g-2 Experiment|
|36||Thursday, December 14, 2017 at 3:00 pm||Seminar Room (C303), Creation Hall (3F), KAIST Munji Campus||Chunglee Kim (KASI)||Exploring the Universe via GWs in the era of multi-messenger astronomy|
|35||2017/03/21 - 06/08||Seminar Room 1323||조길영 박사(KAIST) 외||Spring 2017: Physics Seminar Serises|
|34||2019/09/02 - 12/09||Seminar Room 1501||이호성 박사 (한국표준과학연구원) and etc.||Fall 2019: Physics Colloquium|
|33||2017/03/06 - 05/29||Seminar Room 1501||이종봉 박사 (POSTECH) 외||Spring 2017: Physics Colloquium|
|32||Apr. 27, 2017 (Thu) 4:00 pm||Seminar Room(#1323, E6-2)||Prof.Donghan Lee (Chungnam National Univ.)||반도체 양자점을 이용한 단광자 광원|
|31||Feb.15(Mon), 05:00PM||Zoom||Yoshichika Otani(Tokyo Univ.)||Magnetic Cluster Octupole Domain evolutation in chiral antiferromagnets|
|30||Jan.28(Thu), 03:00PM||Zoom||Yaroslav Tserkovnyak (UCLA)||Topological Transport of Deconfined Hedgehogs in Magnets|
|29||Feb. 2(Tue) 2:30 PM||Zoom||Prof. Sangsik Kim (Texas Tech University, USA)||Quantum- & Nano-Photonics 세미나(Integrated Nanophotonics with Metamaterials, Microcomb, and Atomic Systems)|
|28||Dec.10(Thu), 01:55 PM||Zoom||Yin Wen (University of Tokyo)||Consistency of Boltzmann equation and light dark matter from inflaton decay|
|27||Dec.9(Wed), 10:00AM||Zoom||Prof. Andrew Geraci (Northwestern University)||Searching for the QCD axion with the ARIADNE experiment|
|26||December 2(Wed), 10:00AM||Zoom||Prof. Rakshya Katiwada (Illinois Institute of Technology)||Recent progress in Axion Dark Matter eXperiment (ADMX) technology|
|25||Sep. 11(Fri), 14:00~||zoom||이관형교수/SNU, 이상윤교수/GIST||SRC Seminar|
|24||Jan 12th (Wed), 11:00 AM||Zoom and E6 #1323||Joonseok Hur (MIT)||Spectroscopic study of trapped ions towards probing dark matter and new physics|
|23||Sep. 24(Thu), 09:00~, Sep. 24(Thu), 16:00 ~||Zoom Video||Akash V. Dixit (University of Chicago), Dr. Boris Ivanov (Novosibirsk State Technical University)||(CAPP/IBS)Searching for Dark Matter with a Superconducting Qubit , Cryogenic Microwave Circuit Development at the NSTU|