서브메뉴
검색
Improving the Coherence of Superconducting Quantum Circuits Through Loss Characterization and Design Optimization
Improving the Coherence of Superconducting Quantum Circuits Through Loss Characterization and Design Optimization
상세정보
- 자료유형
- 학위논문 서양
- 최종처리일시
- 20250211150913
- ISBN
- 9798383565131
- DDC
- 530.1
- 서명/저자
- Improving the Coherence of Superconducting Quantum Circuits Through Loss Characterization and Design Optimization
- 발행사항
- [Sl] : Yale University, 2024
- 발행사항
- Ann Arbor : ProQuest Dissertations & Theses, 2024
- 형태사항
- 263 p
- 주기사항
- Source: Dissertations Abstracts International, Volume: 86-02, Section: B.
- 주기사항
- Advisor: Schoelkopf, Robert J.
- 학위논문주기
- Thesis (Ph.D.)--Yale University, 2024.
- 초록/해제
- 요약Realizing a practical quantum computer with superconducting qubits requires substantially higher gate fidelities, which necessitates further improvements in the coherence of superconducting quantum circuits. Steady improvements have been made over the past two decades, including substantial exploration into energy relaxation mechanisms in superconducting thin films. However, a comprehensive and quantitative understanding of the relative impact of these mechanisms does not yet exist. In this thesis, I utilize a multimode approach to systematically characterize microwave losses in the quantum regime, with the goals of understanding relaxation-limiting loss mechanisms and improving device coherence through materials, process, and circuit design optimization. Using this approach, we measure significant reductions in surface losses by employing a tantalum-based materials platform, and in bulk substrate loss by utilizing high-temperature annealing processes. With this knowledge we predict and experimentally verify the relaxation times of aluminum and tantalum-based transmon qubits. We additionally optimize device geometry to maximize coherence within a coaxial tunnel architecture, and realize on-chip quantum memories with single-photon Ramsey times of 2.0 - 2.7 ms, limited by their energy relaxation times of 1.0 - 1.4 ms. This demonstrates an important link between microwave loss characterization and improving coherence in superconducting qubits, and enables a more modular and compact coaxial circuit architecture for bosonic qubits with reproducibly high coherence.
- 일반주제명
- Quantum physics
- 일반주제명
- Low temperature physics
- 일반주제명
- Condensed matter physics
- 키워드
- Coherence
- 키워드
- cQED
- 키워드
- Microwave
- 키워드
- Quantum
- 키워드
- Qubit
- 키워드
- Superconducting
- 기타저자
- Yale University Physics
- 기본자료저록
- Dissertations Abstracts International. 86-02B.
- 전자적 위치 및 접속
- 로그인 후 원문을 볼 수 있습니다.
MARC
008250123s2024 us c eng d■001000017160122
■00520250211150913
■006m o d
■007cr#unu||||||||
■020 ▼a9798383565131
■035 ▼a(MiAaPQ)AAI30693626
■040 ▼aMiAaPQ▼cMiAaPQ
■0820 ▼a530.1
■1001 ▼aGanjam, Suhas Sham.
■24510▼aImproving the Coherence of Superconducting Quantum Circuits Through Loss Characterization and Design Optimization
■260 ▼a[Sl]▼bYale University▼c2024
■260 1▼aAnn Arbor▼bProQuest Dissertations & Theses▼c2024
■300 ▼a263 p
■500 ▼aSource: Dissertations Abstracts International, Volume: 86-02, Section: B.
■500 ▼aAdvisor: Schoelkopf, Robert J.
■5021 ▼aThesis (Ph.D.)--Yale University, 2024.
■520 ▼aRealizing a practical quantum computer with superconducting qubits requires substantially higher gate fidelities, which necessitates further improvements in the coherence of superconducting quantum circuits. Steady improvements have been made over the past two decades, including substantial exploration into energy relaxation mechanisms in superconducting thin films. However, a comprehensive and quantitative understanding of the relative impact of these mechanisms does not yet exist. In this thesis, I utilize a multimode approach to systematically characterize microwave losses in the quantum regime, with the goals of understanding relaxation-limiting loss mechanisms and improving device coherence through materials, process, and circuit design optimization. Using this approach, we measure significant reductions in surface losses by employing a tantalum-based materials platform, and in bulk substrate loss by utilizing high-temperature annealing processes. With this knowledge we predict and experimentally verify the relaxation times of aluminum and tantalum-based transmon qubits. We additionally optimize device geometry to maximize coherence within a coaxial tunnel architecture, and realize on-chip quantum memories with single-photon Ramsey times of 2.0 - 2.7 ms, limited by their energy relaxation times of 1.0 - 1.4 ms. This demonstrates an important link between microwave loss characterization and improving coherence in superconducting qubits, and enables a more modular and compact coaxial circuit architecture for bosonic qubits with reproducibly high coherence.
■590 ▼aSchool code: 0265.
■650 4▼aQuantum physics
■650 4▼aLow temperature physics
■650 4▼aCondensed matter physics
■653 ▼aCoherence
■653 ▼acQED
■653 ▼aMicrowave
■653 ▼aQuantum
■653 ▼aQubit
■653 ▼aSuperconducting
■690 ▼a0599
■690 ▼a0598
■690 ▼a0611
■71020▼aYale University▼bPhysics.
■7730 ▼tDissertations Abstracts International▼g86-02B.
■790 ▼a0265
■791 ▼aPh.D.
■792 ▼a2024
■793 ▼aEnglish
■85640▼uhttp://www.riss.kr/pdu/ddodLink.do?id=T17160122▼nKERIS▼z이 자료의 원문은 한국교육학술정보원에서 제공합니다.
