visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2022-12-09 11:00 
연사  
장소 E6-2 #1323 
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 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)
265 2016-08-04 14:30    Relational Logic (with applications to Quantum Mechanics, String Theory, Cosmology, Neutrino Oscillations, Statistical Mechanics)
264 2021-03-25 16:00    Search for dark matter axion with Rydberg atoms file
263 2023-06-01 16:00    Hall viscosity and topological phenomena
262 2018-07-09 14:00    The principles of collective learning file
261 2023-10-11 16:00    [CAPP seminar] Particle Physics with Neutrinos file
260 2019-05-30 16:00    Tuning the excitonic properties of semiconductors with light-matter interactions file
259 2014-12-22 14:00    Dynamics of molecular motors: Power stroke vs Brownian ratchet file
258 2019-05-03 11:00    Exotic Magnetism file
257 2015-03-04 12:00    Bioimaging and Biosensing Using Near-Infrared Fluorescence file
256 2022-10-04 16:00    Distinguishing 6d (1, 0) SCFTs
255 2023-11-15 16:00    Quantum hydrodynamic theory for plasmonics: from molecule-coupling to nonlinear optics
254 2016-03-07 16:00    Physics Colloquium : 2016 Spring file
253 2019-09-18 16:00    Fall 2019: Physics Seminar Serises file
252 2023-03-30 16:00    Detecting axions with chiral magnetic effects file
251 2019-02-21 16:00    B-meson charged current anomalies - Theoretical status file
250 2023-11-01 16:00    [High Energy Theory Seminar] Modular functions and 3D N=4 rank-zero superconformal field theories
249 2022-09-21 16:00    Materials and Device Nanofabrication of Optical Metasurfaces file
248 2023-03-27 15:00    A coherent mechanical oscillator pumped by a suspended quantum dot file
247 2025-06-26 16:00  Prof. Eun-Ah Kim (Cornell)  Attention to Quantum Complexity file
246 2022-06-03 11:00    (응집물리 세미나) Theoretical Investigation of Exotic Quantum States in Low-dimensional Materials