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
528 2015-11-28 10:00  E6-2, #1323  Electron Tunneling Spectroscopy of Single and Bilayer Graphene with Hexagonal Boron Nitride as Tunneling Barrier
527 2015-12-01 16:00  E6-2, #1323  Introducing extra dimensions to spectroscopic studies of advanced quantum materials
526 2015-12-02 16:00  E6-2, #1323  Samarium Hexaboride: Is it a Topological insulator?
525 2015-12-03 16:00  E6-2, #1323  Hybrid solid state spin qubits in wide bandgap semiconductors
524 2015-12-09 11:00  E4(KI Building), Connect room (2nd fl.)  Functional Imaging & Monitoring of Brain & Breast with Diffuse Light
523 2015-12-09 14:00  E6-2, #1323  SWELLABLE COLLOIDAL PARTICLES ARE SWELL
522 2015-12-11 13:30  E6-2, #1323  Quantum spin liquid in the 1/3 depleted triangular lattice Ba3(Ru1-xIrx)Ti2O9
521 2015-12-11 15:45  E6-2, #1323  Dynamical mean field theory studies on heavy fermion system
520 2015-12-17 11:00  E4(KI Building), Matrix Hall (2nd fl.)  Wavefront engineering for in-vivo Deep brain imaging
519 2016-01-11 16:00  E6-2, #1323  Mott Physics in the Strong Spin-Orbit Coupling Regime
518 2016-01-26 14:00  E6-2, #1323  Electrochemistry on Nano- and Atomic Levels: Scanning Probe Microscopy Meets Deep Data
517 2016-03-07 16:00  E6, 1501  Physics Colloquium : 2016 Spring file
516 2016-03-11 13:30  E6-2, 1501 외  Physics Seminar Serises : 2016 Spring file
515 2016-03-11 13:30  E6-2. 1st fl. #1501  Topological phases of matter in nonequilibrium: Topology of the Wannier-Stark ladder
514 2016-03-11 16:00  E6-2. 1st fl. #1501  Jan. Switching handedness of of chiral solitons in Z4 topological insulators
513 2016-04-01 14:30  E6-2. 1st fl. #1501  Interference of single charged particles without a loop and dynamic nonlocality
512 2016-04-01 16:15  E6-2. 1st fl. #1501  Cotunneling drag effect in Coulomb-coupled quantum dots
511 2016-04-04 09:30  KAIST Natural Science Building (E6-2), RM #4314  Radio frequency engineering
510 2016-04-05 16:00  E6-2. 1st fl. #1322  A new impurity solver for multi-orbital systems: adaptive truncation of the Hilbert space
509 2016-04-06 15:30  E6-2, RM #1323  Superconducting Quantum Interference Devices for Precision Detection