title: Cavity State Manipulation Using Photon-Number Selective Phase Gates.
abstract: The large available Hilbert space and high coherence of cavity resonators make these systems an interesting resource for storing encoded quantum bits. To perform a quantum gate on this encoded information, however, complex nonlinear operations must be applied to the many levels of the oscillator simultaneously. In this work, we introduce the selective number-dependent arbitrary phase (snap) gate, which imparts a different phase to each Fock-state component using an off-resonantly coupled qubit. We show that the snap gate allows control over the quantum phases by correcting the unwanted phase evolution due to the Kerr effect. Furthermore, by combining the snap gate with oscillator displacements, we create a one-photon Fock state with high fidelity. Using just these two controls, one can construct arbitrary unitary operations, offering a scalable route to performing logical manipulations on oscillator-encoded qubits.
authors.affiliation: Departments of Physics and Applied Physics, Yale University, New Haven, Connecticut 06520, USA.
authors.forename: Reinier W
authors.initials: RW
authors.lastname: Heeres
authors.affiliation: Departments of Physics and Applied Physics, Yale University, New Haven, Connecticut 06520, USA.
authors.forename: Brian
authors.initials: B
authors.lastname: Vlastakis
authors.affiliation: Departments of Physics and Applied Physics, Yale University, New Haven, Connecticut 06520, USA.
authors.forename: Eric
authors.initials: E
authors.lastname: Holland
authors.affiliation: Departments of Physics and Applied Physics, Yale University, New Haven, Connecticut 06520, USA.
authors.forename: Stefan
authors.initials: S
authors.lastname: Krastanov
authors.affiliation: Departments of Physics and Applied Physics, Yale University, New Haven, Connecticut 06520, USA.
authors.forename: Victor V
authors.initials: VV
authors.lastname: Albert
authors.affiliation: Departments of Physics and Applied Physics, Yale University, New Haven, Connecticut 06520, USA.
authors.forename: Luigi
authors.initials: L
authors.lastname: Frunzio
authors.affiliation: Departments of Physics and Applied Physics, Yale University, New Haven, Connecticut 06520, USA.
authors.forename: Liang
authors.initials: L
authors.lastname: Jiang
authors.affiliation: Departments of Physics and Applied Physics, Yale University, New Haven, Connecticut 06520, USA.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Schoelkopf