2006/02/28 by Stephen D. Bartlett, Terry Rudolph, Robert W. Spekkens +1 · 2 citations
Computer Science · Physics and Astronomy · #Force Microscopy Techniques and Applications #Mechanical and Optical Resonators #Quantum Information and Cryptography #quant-ph
paper · pdf · doi:10.1088/1367-2630/8/4/058
published as New J. Phys. 8, 58 (2006) · 9 pages plus appendices, 4 figures, published version
openalex publication_date 2006/04/19 · arxiv created 2006/04/20 · arxiv updated 2009/12/01 · openalex created_date 2020/11/23 · openalex updated_date 2026/07/30
We investigate the degradation of reference frames (RFs), treated as dynamical quantum systems, and quantify their longevity as a resource for performing tasks in quantum information processing. We adopt an operational measure of an RF's longevity, namely, the number of measurements that can be made against it with a certain error tolerance. We investigate two distinct types of RF: a reference direction, realized by a spin- j system, and a phase reference, realized by an oscillator mode with bounded energy. For both cases, we show that our measure of longevity increases quadratically with the size of the reference system and is therefore non-additive. For instance, the number of measurements for which a directional RF consisting of N parallel spins can be put to use scales as N 2 . Our results quantify the extent to which microscopic or mesoscopic RFs may be used for repeated, high-precision measurements, without needing to be reset—a question that is important for some implementations of quantum computing. We illustrate our results using the proposed single-spin measurement scheme of magnetic resonance force microscopy.