We consider a basic model of digital memory where each cell is composed of a reflecting medium with two possible reflectivities. By fixing the mean number of photons irradiated over each memory cell, we show that a non-classical source of light can retrieve more information than any classical source. This improvement is shown in the regime of few photons and high reflectivities, where the gain of information can be surprising. As a result, the use of quantum light can have non-trivial applications in the technology of digital memories, such as optical disks and barcodes.
@article{arxiv.1103.3478,
title = {Quantum Reading of a Classical Digital Memory},
author = {Stefano Pirandola},
journal= {arXiv preprint arXiv:1103.3478},
year = {2015}
}
Comments
PRL selected by the APS editors for a synopsis in "Physics". This document is the published Letter only. See arXiv:0907.3398 for a longer document which includes both the Letter (4 pages) and the Supplemental Material (21 pages)