The quantum theory of atoms, molecules and photons

Wolfgang Demtröder

National Research Council

Bengt Nordén

The first two-photon entanglement experiment performed 50 years ago by Kocher and Commins (KC) provided isolated pairs of entangled photons from an atomic three-state fluorescence cascade. In view of questioning of Bell’s theorem, data from these experiments are re-analyzed and shown sufficiently precise to confirm quantum mechanical and dismiss semi-classical theory without need for Bell’s inequalities. Polarization photon correlation anisotropy (A) is useful: A is near unity as predicted quantum mechanically and well above the semi-classic range, 0⩽A⩽1/2. Although yet to be found, one may envisage a three-state molecule emitting entangled photon pairs, in analogy with the KC atomic system. Antibunching in fluorescence from single molecules in matrix and entangled photons from quantum dots promise it be possible. Molecules can have advantages to parametric down-conversion as the latter photon distribution is Poissonian and unsuitable for producing isolated pairs of entangled photons. Analytical molecular applications of entangled light are also envisaged.

Charles H. Holbrow, James N. Lloyd, Joseph C. Amato +2 more

Muslim Fakhruddin

ABSTRACT\nUsing Brownian's motion, Maxwell-Boltzmann' s molecular energy distribution, bohr postulates and Einstein's theory on quantum theory of photon radiation due to the interaction between photons and atoms/molecules accuring at thermal equilibrium, the Einstein's theory on stimulated emission by an exited moving atomic ensemble has been investigated. The modified spectral energy density p of the inducing photons appearing in the plank's law of black body radiation with an additional drag coefficient 7L which accommodates recoil effect of atoms/ molecules when the inducing photons hit them has been derived giving the form\nB":\thv\t\tand .[R„ R,1hv° [1\t1 dln(p) \nB\np(v) =\te v \t\nC2\t3 d In( v)\ne\t—B:\nB:\nThe modification steps which have been done based on momentum equilibrium, have improved the Einstein's theory on stimulated emission semiclassically.\n\nKeywords : stimulated, momentum-equilibrium, black body radiation, drag coefficient, photon spectral energy.

Andreas Hofmann