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
242 2022-12-07 16:00  E6-2 #1323  (광학분야 세미나) Non-Hermitian physics and non-Hermitian singularity
241 2022-10-13 16:00  E6-2 #1323  (광학분야 세미나) Ultrafast Optics for Ultra-Precision Metrology and Realization of Flexible/Stretchable Laser-Induced-Graphene Electronics
240 2024-03-08 11:00  E6-2 #1323  2024 봄학기 광학분야 및 응집물리 특별세미나 전체 일정 file
239 2022-06-03 11:00  E6-2 #1323  (응집물리 세미나) Theoretical Investigation of Exotic Quantum States in Low-dimensional Materials
238 2022-11-03 16:00  E6-2 #1323  (광학분야 세미나) Single-photon emission from low-dimensional materials
237 2023-06-01 16:00  E6-2 #1323  (광학분야 세미나)Quantum sensing using a squeezed light from hot Rb vapor
236 2022-10-28 11:00  E6-2 #1323  [Update 세미나영상] (응집물리 세미나) Machine-Learning-Guided Prediction models and Materials discovery for high Tc cuprates file
235 2022-12-09 11:00  E6-2 #1323  [Update 세미나영상](응집물리 세미나) Single-shot measurements of strongly-correlated artificial molecular levels in semiconductor quantum dots file
234 2023-03-16 16:00  E6-2 #1323  2023 봄학기 광학분야 및 응집물리 특별세미나 전체 일정 file
233 2022-11-25 11:00  E6-2 #1323  [Update 세미나영상](응집물리 세미나) DMFT+ NRG: From models to real materials, from local to nonlocal correlations file
232 2017-10-10 16:00  E6-2 #1323  Discovery of New 2D Materials with Diverse Physical Properties
231 2020-10-23 14:00  E6-2 #1323  Plasmon spectroscopy of low-dimensional superconductors in fluctuating regime file
230 2023-04-27 11:00  E6-2 #1322  Inverse Shapiro steps and coherent quantum phase slip in superconducting nanowires
229 2022-12-13 11:00  E6-2 #1322  Art of thin film engineering toward topological quantum computation file
228 2024-01-26 15:00  E6-2 #1323  In-situ 4D-STEM studies on surface reconstruction and polarization switching of perovskite oxides
227 2023-10-19 11:00  E6-2 #1322  Emergent functionalities of iridium oxide films with different growth orientation file
226 2018-12-26 16:00  E6-1. 3rd fl. #3434  Informal Workshop on Topology and Correlation file
225 2018-10-24 10:30  E6-1, Lecture Room 1501(1F)  Photonic integration of next-generation clocks and Hertz-absolute-accuarcy optical frequenncy synthesizers file
224 2024-02-26 16:00  E6-1 #1501  2024 봄학기 콜로키움 전체 일정 file
223 2023-08-24 12:00  E6-1 #1501  2023 가을학기 콜로키움 전체 일정 file