visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2022-05-13 14:30 
연사  
장소 Zoom webinar 

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 연사 제목
공지 2025-02-24 16:00    2025년 봄학기 콜로키움 안내
공지 2025-02-27 16:00    2025년 봄 물리학과 특별세미나 (광학/응집물리 분야)
505 2012-04-02 16:00    A new route to ferroelectricity in magnetic spinels: a case of Co2MnO4
504 2024-11-18 10:30    Manipulation of antiferromagnetic magnon polarization in synthetic antiferromagnets
503 2020-12-10 13:55    Consistency of Boltzmann equation and light dark matter from inflaton decay
502 2016-09-05 16:00    Physics Colloquium : 2016 Fall file
501 2024-07-03 16:00    [High Energy Theory Seminar] Holographic duals of Higgsed Dpb(BCD)
500 2021-01-28 15:00    Topological Transport of Deconfined Hedgehogs in Magnets file
499 2018-12-26 16:00    Informal Workshop on Topology and Correlation file
498 2021-06-22 17:00    Spintronics meets Quantum Materials file
497 2024-12-06 16:00  Vladimir Y. Chernyak  Bright Squeezed Light (BSL) Spectroscopy with Interferometry from First Principles
496 2021-06-08 10:00    Photonic crystal devices for sensing file
495 2023-06-30 11:00    The Dual Mode Quantum Computer file
494 2023-11-29 10:00    [High Energy Theory Seminar] Averaged null energy and the renormalization group
493 2020-09-14 17:30    KAIST Global Forum for Spin and Beyond (Third Forum) file
492 2024-11-13 12:00    [11/13(수) 물리학과 세미나 안내] Separability as a window to mixed-state quantum phases and phase transitions / Tarun Grover (UC San Diego, Associate Professor)
491 2022-11-03 13:00    [High-Energy Theory Seminar] Supersymmetric observables via Fermi-gas method
490 2024-10-31 13:00    Mini-workshop on first-principles DFT methods and applications
489 2019-07-08 14:00    Ultrabroadband squeezed pulses and their relation to relativity file
488 2023-04-05 16:00    [High Energy Theory Seminar]Anomalies of Discrete 1-Form Symmetries in QCD-like Theories
487 2024-03-27 16:00    [High Energy Theory Seminar] The Callan Rubakov Effect
486 2023-02-20 17:00    (Optics Seminar) Neural Holography for Next generation Virtual and Augmented Reality Displays file