Issue
EPL
Volume 82, Number 1, April 2008
Article Number 18003
Number of page(s) 6
Section Interdisciplinary Physics and Related Areas of Science and Technology
DOI http://dx.doi.org/10.1209/0295-5075/82/18003
Published online 12 March 2008
EPL, 82 (2008) 18003
DOI: 10.1209/0295-5075/82/18003

Energy measurements and preparation of canonical phase states of a nano-mechanical resonator

K. Jacobs1, 2, A. N. Jordan3 and E. K. Irish4

1  Department of Physics, University of Massachusetts at Boston - 100 Morrissey Blvd, Boston, MA 02125, USA
2  Quantum Science and Technologies Group, Hearne Institute for Theoretical Physics, Louisiana State University 202 Nicholson Hall, Tower Drive, Baton Rouge, LA 70803, USA
3  Department of Physics and Astronomy, University of Rochester - Rochester, NY 14627, USA
4  School of Mathematics and Physics, Queens University Belfast - Belfast, BT7 1NN, UK, EU

kurt.jacobs@umb.edu

received 17 September 2007; accepted in final form 15 February 2008; published April 2008
published online 12 March 2008

Abstract
We show that a continuous quantum non-demolition measurement of the energy of a nanomechanical resonator can be achieved by monitoring the resonator with a single-electron transistor, or a quantum point contact, via a Cooper-pair box. This technique can further be used to prepare highly entangled states of two resonators, such as canonical phase reference states, and so-called noon states.

PACS
85.85.+j - Micro- and nano-electromechanical systems (MEMS/NEMS) and devices.
85.35.Gv - Single electron devices.
03.65.Ta - Foundations of quantum mechanics; measurement theory.

© EPLA 2008