Control of photon emission from single molecules and planar materials

Baiping Han, Yujun Zheng

Takahiro Kaji

C. Begon, Hervé Rigneault, Per Jonsson +1 more

We report on the interest of spontaneous emission control with planar dielectric multi-layer structures to increase the fluorescence collection efficiency in single-molecule detection experiments and ultrasensitive analysis. The effect of a very simple Fabry Perot microcavity on the radiation pattern of Eu3+ chelate molecules is introduced and discussed. Then the fluorescence correlation spectroscopy (FCS) technique is used to detect Cyanine 5 molecules on a simple mirror and Rhodamine 6G (R6G) molecules in a microcavity, both in liquid solutions. The respective advantages of those dielectric structures for increasing the count rate per molecule are described. The detection enhancement is used to demonstrate photon antibunching on the nanosecond time scale with a dilute solution of R6G molecules (10-9 M) in the microcavity.

Ho Trung Dung, L. Knöll, Dirk‐Gunnar Welsch

A three-dimensional (3D) analysis of the spontaneous decay of a single dipole embedded in a planar multilayer structure is given, with special emphasis on Kerr-tunable photonic band-gap materials for single-photon emission on demand. It is shown that the change in the density of states near a defect resonance is much more pronounced than that near the band edges. In particular, operation near the band edge as suggested from a 1D analysis is little suited for controlling the photon emission.

W. E. Moerner

Single molecules in suitable host crystals have been demonstrated to be useful single-photon emitters both at liquid-helium temperatures and at room temperature. The low-temperature source achieved controllable emission of single photons from a single terrylene molecule in p -terphenyl by an adiabatic rapid passage technique. In contrast with almost all other single-molecule systems, terrylene single molecules show extremely high photostability under continuous, high-intensity irradiation. A room-temperature source utilizing this material has been demonstrated, in which fast pumping into vibrational sidebands of the electronically excited state achieved efficient inversion of the emissive level. This source yielded a single-photon emission probability p (1) of 0.86 at a detected count rate near 300 000 photons s −1 , with very small probability of emission of more than one photon. Thus, single molecules in solids can be considered as contenders for applications of single-photon sources such as quantum key distribution.