Theory of entangled two-photon emission/absorption [E2P-EA] between molecules

Tse-Min Chiang; George C Schatz

doi:10.1063/5.0156501

Theory of entangled two-photon emission/absorption [E2P-EA] between molecules

J Chem Phys. 2023 Aug 21;159(7):074103. doi: 10.1063/5.0156501.

Authors

Tse-Min Chiang¹, George C Schatz²

Affiliations

¹ Graduate Program in Applied Physics, Northwestern University, Evanston, Illinois 60208, USA.
² Department of Chemistry and Graduate Program in Applied Physics, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA.

PMID: 37581420
DOI: 10.1063/5.0156501

Abstract

This paper presents a comprehensive study of the theory of entangled two-photon emission/absorption (E2P-EA) between a many-level cascade donor and a many-level acceptor (which could be quantum dots or molecules) using second-order perturbation theory and where the donor-acceptor pair is in a homogeneous but dispersive medium. To understand the mechanism of E2P-EA, we analyze how dipole orientation, radiative lifetime, energy detuning between intermediate states, separation distance, and entanglement time impact the E2P-EA rate. Our study shows that there are quantum interference effects in the E2P-EA rate expression that lead to oscillations in the rate as a function of entanglement time. Furthermore, we find that the E2P-EA rate for a representative system consisting of two quantum dots can be comparable to one-photon emission/absorption (OP-EA) when donor and acceptor are within a few nm. However, the E2P-EA rate falls off much more quickly with separation distance than does OP-EA.