Relation between fundamental estimation limit and stability in linear quantum systems with imperfect measurement
| dc.creator | Yamamoto, Naoki | |
| dc.creator | Hara, Shinji | |
| dc.date | 2007-09-21 | |
| dc.date.accessioned | 2026-07-07T08:31:25Z | |
| dc.date.available | 2026-07-07T08:31:25Z | |
| dc.description | From the noncommutative nature of quantum mechanics, estimation of canonical observables $\hat{q}$ and $\hat{p}$ is essentially restricted in its performance by the Heisenberg uncertainty relation, $\mean{Δ\hat{q}^2}\mean{Δ\hat{p}^2}\geq \hbar^2/4$. This fundamental lower-bound may become bigger when taking the structure and quality of a specific measurement apparatus into account. In this paper, we consider a particle subjected to a linear dynamics that is continuously monitored with efficiency $η\in(0,1]$. It is then clarified that the above Heisenberg uncertainty relation is replaced by $\mean{Δ\hat{q}^2}\mean{Δ\hat{p}^2}\geq \hbar^2/4η$ if the monitored system is unstable, while there exists a stable quantum system for which the Heisenberg limit is reached. | |
| dc.description | 4 pages | |
| dc.identifier | https://arxiv.org/abs/0709.3352 | |
| dc.identifier | http://arxiv.org/abs/0709.3352 | |
| dc.identifier | Physical Review A 76, 034102 (2007) | |
| dc.identifier | doi:10.1103/PhysRevA.76.034102 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/138496 | |
| dc.subject | Quantum Physics | |
| dc.title | Relation between fundamental estimation limit and stability in linear quantum systems with imperfect measurement | |
| dc.type | text |