visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2022-12-09 11:00 
일시 Dec. 9 (Fri), 11:00AM 
장소 E6-2 #1323 
연사 김도헌(서울대 물리천문학부 교수) 
세미나 영상은 아래 링크로 확인 바랍니다. (공개기간: 2022.12.15-2023.03.14, 3개월)
 
 
1. Date / Time 
    - Dec  9, 2022
    - 11:00 AM (KST)
 
2. Place: E6-2 #1323
 
3. Speaker
    - 김도헌 (서울대 물리천문학부 교수)
 
4. Talk Title
    - Two-electron quantum dot spin qubits in isotopically purified silicon
 
5. Abstract
Engineered spin-electric coupling is essential to enable fast manipulation of spins in semiconductor quantum dot (QD) nanostructures, especially in silicon. Although the placement of on-chip micromagnets has enabled single-spin qubits in silicon with gate fidelity to reach surface code-based error correction threshold, corresponding results using encoded spin qubits, for example, single-triplet qubits with high-quality quantum oscillations, have not been demonstrated. Instead, the spin-valley coupling has been recently used to enhance the electrical controllability of two-electron spin qubits in silicon at the expense of increased susceptibility to charge noise. Here, we demonstrate fast singlet-triplet qubit oscillation (~ 100MHz) of a quantum dot spin qubit in isotopically purified 28Si/SiGe substrate with an on-chip micromagnet in the regime where valley-splitting in each quantum dot exceeds 300 ueV. Combining rf-reflectometry-based single-shot readout and real time Hamiltonian estimation, we show that the oscillation quality factor of an encoded spin qubit over 1000 can be achieved. We further present the measurement of single-triplet qubit oscillation and variation of coherence time near the micro-magnet’s magnetization reversal, offering a route to in-situ tune magnetic field gradient and hence the Larmor frequency of the singlet-triplet qubit in silicon.
 
Attached: C.V
 
Inquiry: Prof. Se Kwon Kim(sekwonkim@kaist.ac.kr) / Prof. Hee Jun Yang (h.yang@kaist.ac.kr)
 
번호 날짜 장소 제목
342 2017-12-15 09:20  E6-2, Lecture Room #1323  Workshop on Magnetism in Unconventional Superconductors 개최 file
341 2015-10-16 15:00  E6-2, 5th fl. #5318  High Magnetic Fields to Probe the sub-eV range of Particle/Astroparticle Physics - From the OSQAR experiments at CERN up to new perspectives at LNCMI-Grenoble
340 2015-10-15 10:00  E6-2, 5th fl. #5318  Development of Large-Bore, High Field Magnets at the NHMFL
339 2018-06-14 10:00  E6-2, 2nd fl. #2502  Phonons and polariton-like particles in trapped ions for quantum computation and quantum simulation file
338 2019-07-03 15:00  E6-2, 2501  Many-body quantum electrodynamis (QED) with atoms and photons: A new platform for quantum optics" file
337 2016-03-11 13:30  E6-2, 1501 외  Physics Seminar Serises : 2016 Spring file
336 2015-07-16 16:00  E6-2, 1501  KAIST Physics Distinguished Lecture
335 2015-07-16 16:00  E6-2, 1318  Next-generation ultrafast laser technology for nonlinear optics and strong-field physics
334 2020-02-12 13:00  E6-2, #5318  From inflation to new weak-scale file
333 2015-11-06 16:30  E6-2, #5318  Topological Dirac line nodes in centrosymmetric semimetals
332 2015-10-23 15:00  E6-2, #5318  Development of a Rogowski Coil as a new beam position monitor
331 2023-11-22 10:00  E6-2, #5301 & zoom  [High Energy Theory Seminar] Exact Quantum Algorithms to Recognize Quantum Phases of Matter
330 2023-06-01 16:00  E6-2, #5301  Hall viscosity and topological phenomena
329 2024-03-27 16:00  E6-2, #2502  [High Energy Theory Seminar] The Callan Rubakov Effect
328 2023-09-13 16:00  E6-2, #2502  [High Energy Theory Seminar] Cosmic Birefringence from Dark Photon
327 2023-05-31 16:00  E6-2, #2502  [High-Energy Theory Seminar] Resurgence and complex Chern-Simons theory
326 2024-01-16 16:00  E6-2, #2502  [High Energy Theory Seminar] Towards quantum black hole microstates
325 2023-04-05 16:00  E6-2, #2502  [High Energy Theory Seminar]Anomalies of Discrete 1-Form Symmetries in QCD-like Theories
324 2023-03-22 16:00  E6-2, #2502  (High Energy Theory Seminar) Boltzmann or Bogoliubov? A Case of Gravitational Particle Production
323 2023-11-22 16:00  E6-2, #2502  [High Energy Theory Seminar] Renormalization and the Hierarchy Problem