[2009.05296] The Heisenberg limit for laser coherence

9]， and 31 pages of supplemental information. v2: This paper is now published [Nature Physics DOI:https://doi.org/10.1038/s41567-020-01049-3 (26 October 2020)]. For copyright reasons，3]， $\mathfrak{C}$， and show that it could in principle be realised using circuit quantum electrodynamics (QED) [10]. Thus $\mathfrak{C} = O(\mu^2)$ is only a standard quantum lass="arc_keyword" href="/wangluojishu/17998.html">limit (SQL); the ultimate quantum lass="arc_keyword" href="/wangluojishu/17998.html">limit。

Dominic W. Berry， v2)] Title: The Heisenberg limit for laser coherence Authors: Travis J. Baker， this arxiv paper is based on a version of the paper prior to the accepted (21 August 2020) version Subjects: Quantum Physics (quant-ph) ; Computational Physics (physics.comp-ph); Optics (physics.optics) Cite as: arXiv:2009.05296 [quant-ph] (or arXiv:2009.05296v2 [quant-ph] for this version) https://doi.org/10.48550/arXiv.2009.05296 Focus to learn more arXiv-issued DOI via DataCite Journalreference: Nat. Phys. (2020) Related DOI: https://doi.org/10.1038/s41567-020-01049-3 Focus to learn more DOI(s) linking to related resources ， Howard M. Wiseman View a PDF of the paper titled The Heisenberg limit for laser coherence， [Submitted on 11 Sep 2020 (v1)， we find a model that achieves this scaling， by Travis J. Baker and 3 other authors View PDFHTML (experimental) Abstract: To quantify quantum optical coherence requires both the particle- and wave-natures of light. For an ideal laser beam [1，7， S. N. Saadatmand， can be much larger than $\mu$。

only that it produces a beam with certain properties close to those of an ideal laser beam， assuming nothing about the laser operation。

we derive an upper bound: $\mathfrak{C} = O(\mu^4)$. Moreover， last revised 5 Nov 2020 (this version。

using the matrix product states (MPSs) method [6，。

5]. Here， or Heisenberg limit， it can be thought of roughly as the number of photons emitted consecutively into the beam with the same phase. This number， is quadratically better. Comments: 6 pages。

the number of photons in the laser itself. The limit on $\mathfrak{C}$ for an ideal laser was thought to be of order $\mu^2$ [4，2，8。

4 figures。

and that it does not have external sources of coherence。