Journal Article

FZJ-2014-01940

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Stochastic-master-equation analysis of optimized three-qubit nondemolition parity measurements

Tornberg, L. (Corresponding Author) ; Barzanjeh, S. ; DiVincenzo, D.FZJ*

2014
APS College Park, Md.

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Please use a persistent id in citations: http://hdl.handle.net/2128/5975  doi:10.1103/PhysRevA.89.032314

Abstract: We analyzea direct parity measurement of the state of three superconducting qubits in circuit quantum electrodynamics. The parity is inferred from a homodyne measurement of the reflected and transmitted microwave radiation, and the measurement is direct in the sense that the parity is measured without the need for any quantum circuit operations or for ancilla qubits. Qubits are coupled to two resonant-cavity modes, allowing the steady state of the emitted radiation to satisfy the necessary conditions to act as a pointer state for the parity. However, the transient dynamics violates these conditions, and we analyze this detrimental effect and show that it can be overcome in the limit of a weak measurement signal. Our analysis shows that, with a moderate degree of postselection, it is possible to achieve postmeasurement states with fidelity of order 95%. We believe that this type of measurement could serve as a benchmark for future error correction protocols in a scalable architecture

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Contributing Institute(s):

1. Theoretische Nanoelektronik (PGI-2)
2. Theoretische Nanoelektronik (IAS-3)
3. JARA-FIT (JARA-FIT)

Research Program(s):

1. 422 - Spin-based and quantum information (POF2-422) (POF2-422)

Appears in the scientific report 2014

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Database coverage:
; ; ; JCR ; Nationallizenz ; SCOPUS ; Science Citation Index ; Science Citation Index Expanded ; Thomson Reuters Master Journal List ; Web of Science Core Collection ; Zoological Record

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