Observation of scalable sub-Poissonian-field lasing in a microlaser

Sub-Poisson field with much reduced fluctuations in a cavity can boost quantum precision measurements via cavity-enhanced light-matter interactions. Strong coupling between an atom and a cavity mode has been utilized to generate highly sub-Poisson fields. However, a macroscopic number of optical intracavity photons with more than 3 dB variance reduction has not been possible. Here, we report sub-Poisson field lasing in a microlaser operating with hundreds of atoms with well-regulated atom-cavity coupling and interaction time. Its photon-number variance was 4 dB below the standard quantum limit while the intracavity mean photon number scalable up to 600. The highly sub-Poisson photon statistics were not deteriorated by simultaneous interaction of a large number of atoms. Our finding suggests an effective pathway to widely scalable near-Fock-state lasing at the macroscopic scale.

Free Poisson fields and their automorphisms

Let [Formula: see text] be an arbitrary field of characteristic [Formula: see text]. We prove that the group of automorphisms of a free Poisson field [Formula: see text] in two variables [Formula: see text] over [Formula: see text] is isomorphic to the Cremona group [Formula: see text]. We also prove that the universal enveloping algebra [Formula: see text] of a free Poisson field [Formula: see text] is a free ideal ring and give a characterization of the Poisson dependence of two elements of [Formula: see text] via universal derivatives.