Consequences of origin dependence for photon-counting observables

Determine the consequences of coherent-displacement and coordinate-origin dependence in cavity-coupled molecular photon-number descriptions for photon-counting observables.

Background

The paper explains that raw photon moments, including photon number and the degree of second-order coherence, depend on the coordinate origin for charged molecules and on the convention used for the molecular dipole. Prior work identified origin-tunable Poissonian photon-number distributions for cavity-coupled ions and analyzed their dependence through Fock-space convergence. The paper introduces displacement-invariant central moments and higher cumulants as a resolution for defining intracavity photon statistics, but it does not resolve how the preceding origin-dependence results bear on photon-counting observables.

Resolving this problem would clarify the relationship between convention-dependent photon-number distributions and physically meaningful photon-counting measurements, particularly for molecular ions and other systems in which coherent displacement changes the raw photon observables.