13 September 2016 Quantum decoherence of a single ion qubit induced by photon-number fluctuations
Author Affiliations +
Abstract
Quantum measurement is based on the interaction between a quantum object and a meter entangled with the object. While information about the object is being extracted by the interaction, the quantum fluctuations of the object are imprinted onto the meter as a form of decoherence. Here, we study the nondestructive reconstruction of the photon number in an optical cavity, harnessing the quantum decoherence. We consider a single 40Ca+ ion that is dispersively coupled to a high-finesse cavity. While the cavity is populated with weak coherent states, Ramsey spectroscopy is performed on the qubit transition to identify the shift and the broadening of the atomic energy levels. The shift is due to the ac Stark effect induced by cavity photons, and the broadening is attributed to the photon-number fluctuations of the cavity field. We show theoretically that photon-number distributions of the intracavity fields can be reconstructed in a basis of up to eleven Fock states with the maximum likelihood method. Furthermore, we show that the photon number of each polarization component can also be reconstructed, taking advantage of the rich energy-level structure of the ion. In combination with currently available mirror-coating technology, quantum non-demolition (QND) measurement of cavity photons will make it possible to create and manipulate nonclassical cavity-field states in the optical domain.
Conference Presentation
© (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Moonjoo Lee, Konstantin Friebe, Florian R. Ong, Dario A. Fioretto, Klemens Schüppert, Rainer Blatt, Tracy E. Northup, "Quantum decoherence of a single ion qubit induced by photon-number fluctuations", Proc. SPIE 9980, Quantum Communications and Quantum Imaging XIV, 99800D (13 September 2016); doi: 10.1117/12.2238503; https://doi.org/10.1117/12.2238503
PROCEEDINGS
7 PAGES + PRESENTATION

SHARE
Back to Top