The Heisenberg limit for laser coherence

• URL: http://arxiv.org/abs/2009.05296v2
• Date: Thu, 5 Nov 2020 12:59:03 GMT
• Title: The Heisenberg limit for laser coherence
• Authors: Travis J. Baker, S. N. Saadatmand, Dominic W. Berry, Howard M. Wiseman
• Abstract summary: Limit on $mathfrakC$ for an ideal laser was thought to be of order $mu2$. We derive an upper bound: $mathfrakC = O(mu4)$.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: To quantify quantum optical coherence requires both the particle- and wave-natures of light. For an ideal laser beam [1,2,3], it can be thought of roughly as the number of photons emitted consecutively into the beam with the same phase. This number, $\mathfrak{C}$, can be much larger than $\mu$, the number of photons in the laser itself. The limit on $\mathfrak{C}$ for an ideal laser was thought to be of order $\mu^2$ [4,5]. Here, assuming nothing about the laser operation, only that it produces a beam with certain properties close to those of an ideal laser beam, and that it does not have external sources of coherence, we derive an upper bound: $\mathfrak{C} = O(\mu^4)$. Moreover, using the matrix product states (MPSs) method [6,7,8,9], we find a model that achieves this scaling, 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 limit (SQL); the ultimate quantum limit, or Heisenberg limit, is quadratically better.

Related papers

• Analytical results for laser models producing a beam with sub-Poissonian photon statistics and coherence scaling as the Heisenberg limit [0.0]
  We characterize the dynamics of each laser system, and find that some of the intuitions from standard laser theory may be applied here. Unlike a standard laser, however, we find that the pure states comprising the ensemble in the Heisenberg-limited lasers are substantially phase squeezed.
  arXiv  Detail & Related papers  (2025-02-24T06:29:40Z)
• Towards large-scale quantum optimization solvers with few qubits [59.63282173947468]
  We introduce a variational quantum solver for optimizations over $m=mathcalO(nk)$ binary variables using only $n$ qubits, with tunable $k>1$. We analytically prove that the specific qubit-efficient encoding brings in a super-polynomial mitigation of barren plateaus as a built-in feature.
  arXiv  Detail & Related papers  (2024-01-17T18:59:38Z)
• Optimized Laser Models with Heisenberg-Limited Coherence and Sub-Poissonian Beam Photon Statistics [0.0]
  We introduce three new families of laser models which may be considered as generalizations of those presented in this paper. We explore the influence of these parameters on both the coherence and photon statistics of the laser beams.
  arXiv  Detail & Related papers  (2022-08-30T08:51:57Z)
• No Tradeoff between Coherence and Sub-Poissonianity for Heisenberg-Limited Lasers [0.0]
  Heisenberg limit to laser coherence $mathfrakC$ is the number of photons in the maximally populated mode of the laser beam. We generalize the previous proof of this upper bound scaling by dropping the requirement that the beam photon statistics be Poissonian. We show that the relation between $mathfrakC$ and sub-Poissonianity ($Q0$) is win-win, not a tradeoff.
  arXiv  Detail & Related papers  (2022-08-30T08:51:51Z)
• On parametric resonance in the laser action [91.3755431537592]
  We consider the selfconsistent semiclassical Maxwell--Schr"odinger system for the solid state laser. We introduce the corresponding Poincar'e map $P$ and consider the differential $DP(Y0)$ at suitable stationary state $Y0$.
  arXiv  Detail & Related papers  (2022-08-22T09:43:57Z)
• Quantum density matrix theory for a laser without adiabatic elimination of the population inversion: transition to lasing in the class-B limit [62.997667081978825]
  No class-B quantum density-matrix model is available to date, capable of accurately describing coherence and photon correlations within a unified theory. Here we carry out a density-matrix theoretical approach for generic class-B lasers, and provide closed equations for the photonic and atomic reduced density matrix in the Fock basis of photons. This model enables the study of few-photon bifurcations and non-classical photon correlations in class-B laser devices, also leveraging quantum descriptions of coherently coupled nanolaser arrays.
  arXiv  Detail & Related papers  (2022-05-26T16:33:51Z)
• Experimental test of the third quantization of the electromagnetic field [0.0]
  An approach was recently introduced in which the wave function $smallpsi_j(x_j)$ was further quantized to produce a field operator $smallhat psi_j(x_j)$. Here we report the results of an optical scattering experiment that set an upper bound of $smallgammaleq 1.93 times 10-4$ at the 99% confidence level.
  arXiv  Detail & Related papers  (2022-01-17T19:47:09Z)
• Rapid generation of all-optical $^{39}$K Bose-Einstein condensates using a low-field Feshbach resonance [58.720142291102135]
  We investigate the production of all-optical $39$K Bose-Einstein condensates with different scattering lengths using a Feshbach resonance near $33$ G. We are able to produce fully condensed ensembles with $5.8times104$ atoms within $850$ ms evaporation time at a scattering length of $232. Based on our findings we describe routes towards high-flux sources of ultra-cold potassium for inertial sensing.
  arXiv  Detail & Related papers  (2022-01-12T16:39:32Z)
• Entanglement between a telecom photon and an on-demand multimode solid-state quantum memory [52.77024349608834]
  We show the first demonstration of entanglement between a telecom photon and a collective spin excitation in a multimode solid-state quantum memory. We extend the entanglement storage in the quantum memory for up to 47.7$mu$s, which could allow for the distribution of entanglement between quantum nodes separated by distances of up to 10 km.
  arXiv  Detail & Related papers  (2021-06-09T13:59:26Z)
• Distinguishing limit of Bell states for any $n$-photon $D$-dimensional hyperentanglement [4.446626375802735]
  Bell state measurement is crucial to quantum information protocols. It is impossible to unambiguously distinguish all the Bell states encoded in multi-photon using only linear optics.
  arXiv  Detail & Related papers  (2020-11-26T11:43:44Z)
• Quantum Simulation of 2D Quantum Chemistry in Optical Lattices [59.89454513692418]
  We propose an analog simulator for discrete 2D quantum chemistry models based on cold atoms in optical lattices. We first analyze how to simulate simple models, like the discrete versions of H and H$+$, using a single fermionic atom. We then show that a single bosonic atom can mediate an effective Coulomb repulsion between two fermions, leading to the analog of molecular Hydrogen in two dimensions.
  arXiv  Detail & Related papers  (2020-02-21T16:00:36Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.