Adaptive Phase Measurements
| dc.creator | Berry, Dominic | |
| dc.date | 2002-02-25 | |
| dc.date.accessioned | 2026-07-07T06:03:44Z | |
| dc.date.available | 2026-07-07T06:03:44Z | |
| dc.description | In this thesis I consider the general problem of how to make the best possible phase measurements using feedback. Both the optimum input state and optimum feedback are considered for both single-mode dyne measurements and two-mode interferometric measurements. I derive the optimum input states under general dyne measurements when the mean photon number is fixed, both for general states and squeezed states. I propose a new feedback scheme that introduces far less phase uncertainty than mark II feedback, and is very close to the theoretical limit. I also derive results for the phase variance when there is a time delay in the feedback loop, showing that there is a lower limit to the introduced phase variance, and this is approached quite accurately under some conditions. I derive the optimum input states for interferometry, showing that the phase uncertainty scales as 1/N for all the common measures of uncertainty. This is contrasted with the |j0>_z state, which does not scale as 1/N for all measures of phase uncertainty. I introduce an adaptive feedback scheme that is very close to optimum, and can give scaling very close to 1/N for the uncertainty. Lastly I consider the case of continuous measurements, for both the dyne and interferometric cases. | |
| dc.description | PhD thesis, 228 pages, 103 figures | |
| dc.identifier | https://arxiv.org/abs/quant-ph/0202136 | |
| dc.identifier | http://arxiv.org/abs/quant-ph/0202136 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/90054 | |
| dc.subject | Quantum Physics | |
| dc.title | Adaptive Phase Measurements | |
| dc.type | text |