Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Conference on Lasers and Electro-Optics

Single Photons from Single Molecules: Hong-Ou-Mandel Experiments and Beyond

Mohammad Rezai, Jörg Wrachtrup, Ilja Gerhardt

Published Jan 1, 2017• 0 citations
Publisher

Abstract

The generation of non-classical light, especially of single photon states, is mostly limited to non-linear optics in crystals and single emitters. Here we perform research on single organic dye molecules under cryogenic conditions. The molecules are well-behaved and do not blink or bleach. Also they exhibit an enormous brightness (>106 detected counts per second) and have narrow-band emission (<15-20MHz). By atomic sodium vapor we are able to suppress unwanted background emission from residual impurities in the sample. This light is now analyzed for the use in all-optical gates and further quantum optical schemes. A first step is the characterization in a Hong-Ou-Mandel type experiment. Different variations of this are possible – reaching from indistinguishable to distinguishable photons impinging on a beam-splitter.

DOI
10.1364/cleo_qels.2017.ftu1e.7

Related papers

Polarization-entangled photon pairs from a single molecule

Ilja Gehardt, Mohammad Rezai, Guilherme Stein +2 more

Single organic dye molecules have been studied for almost three decades. A majority of experiments are now conducted under ambient conditions and aim towards material science and micro-biology. The experiments under cryogenic conditions are often based on highly rigid polycyclic hydrocarbons, which have excellent fluorescing properties when they are operated at temperatures below 2 K. Their photonic advantages integrate their high flux, their narrow-band nature and their tunability over the entire visible spectrum. Therefore the use of organic molecules as efficient and narrow-band single photon sources facilitated a number of quantum optical advances in the past years. The results mostly cover quantum sensing, the formation of quantum hybrid systems and the optical combination of multiple photons in all-optical experiments. Here we present all three fields and outline our own experiments in the combination of single molecule studies, atomic spectroscopy and entanglement generation. The brightness and the narrow-band nature of the molecules are outlined and a delayed-choice quantum eraser is presented. The mode-mixing of two photons on a beam-splitter allows for the generation of a degenerate photon pair, which is resonant to the sodium D2-line. Furthermore, its spectral width matches roughly to the natural linewidth of an isolated sodium atom, such that further experiments are feasible. The entanglement of the post-selected photon pair is testified by a violation of Bell's inequality. Even the raw collected clicks violate Bell's inequality by more than two standard deviations.

Optical and Quantum Sensing and Precision Metrology II•Mar 1, 2019•2 citations

Indistinguishable photons on demand from an organic dye molecule

Pietro Lombardi, Maja Colautti, Rocco Duquennoy +3 more

Single molecules in solid-state matrices have been proposed as sources of single-photon Fock states back 20 years ago. Their success in quantum optics and in many other research fields stems from the simple recipes used in the preparation of samples, with hundreds of nominally identical and isolated molecules. Main challenges as of today for their application in photonic quantum technologies are the optimization of light extraction and the on-demand emission of indistinguishable photons. We here present Hong-Ou-Mandel experiments with photons emitted by a single molecule of dibenzoterrylene in an anthracene nanocrystal at 3 K, under continuous wave and also pulsed excitation. A detailed theoretical model is applied, which relies on independent measurements for most experimental parameters, hence allowing for an analysis of the different contributions to the two-photon interference visibility, from residual dephasing to spectral filtering.

arXiv:2102.13055•Feb 25, 2021•1 citation

Triggered emission of indistinguishable photons from an organic dye molecule

Pietro Lombardi, Maja Colautti, Rocco Duquennoy +3 more

Single molecules in solid state matrices have been proposed as sources of single photon Fock states back 20 years ago. Their success in quantum optics and in many other research fields stems from the simple recipes used in the preparation of samples, with hundreds of nominally identical and isolated molecules. Main challenges as of today for their application in photonic quantum technologies are the optimization of light extraction and the on-demand emission of indistinguishable photons. We here present Hong–Ou–Mandel (HOM) experiments with photons emitted by a single molecule of dibenzoterrylene in an anthracene nanocrystal at 3 K, under continuous wave and also pulsed excitation. A detailed theoretical model is applied, which relies on independent measurements for most experimental parameters, hence allowing for an analysis of the different contributions to the two-photon interference visibility, from residual dephasing to spectral filtering. A HOM interference visibility of more than 75% is reported, which, according to the model, is limited by the residual dephasing present at the operating temperature.

Applied Physics Letters•May 17, 2021•36 citations

Organic Dye Molecules as Single Photon Sources for Optical Quantum Technologies

Pietro Lombardi, R. Emadi, Rocco Duquennoy +3 more

We present Hong-Ou-Mandel (HOM) experiments with photons emitted by a single molecule of Dibenzoterrylene in an Anthracene nanocrystal under pulsed excitation, and preliminary results for photons emitted by two spatially-separated molecules on the same sample.

Quantum Information and Measurement (QIM)•Jan 1, 2021•1 citation

An atomic spectrum recorded with a single-molecule light source

Wilhelm Kiefer, Mohammad Rezai, Jörg Wrachtrup +1 more

A single molecule under cryogenic conditions allows one to realize an extremely bright and simultaneously narrow-band single-photon source. We present a review on the different excitation schemes of a single molecule and present the corresponding single-photon nature of the emitted light. Single-molecule spectroscopy has been recently interlinked with atomic spectroscopy. This optical interconnect among the different quantum systems might be enhanced by a so-called Faraday anomalous dispersion optical filter—an ideal tool for many experiments in quantum optics. We introduce our theoretical and experimental approach on these filters which are based on hot atomic sodium vapor. The electrical tunability together with the brightness of a single molecule allows us to record a full atomic spectrum of this filter with the single photons originating from a single-molecular emitter.

Applied Physics B•Feb 1, 2016•22 citations

Narrow-Band Fiber-Coupled Single-Photon Source

Guilherme Stein, Vladislav Bushmakin, Yijun Wang +2 more

A single-photon source is an essential tool for the emerging field of quantum technologies. Ideally, it should be spectrally compatible with other photonic devices while providing a high flux of narrow-band photons. The single organic dye molecule dibenzanthanthrene under cryogenic conditions possesses the given characteristics and therefore constitutes a prominent single-photon source. Nevertheless, the implementation of such a single-photon source requires a complex experimental setup involving a cryostat with a confocal microscope for the effective collection of the molecular emission. In the approach presented here we use a single emitter coupled directly to the end facet of an optical fiber. This has the potential to transfer a single-photon source based on a quantum emitter from a proof-of-principle type of setup to a scalable ``plug-and-play'' device. We present successful coupling of a single organic molecule to an optical fiber and record the excitation spectrum, measure the saturation curve, and analyze the contributions of Raman background fluorescence. The single-photon nature is proven by an antibunched autocorrelation recording, which reveals coherent Rabi oscillations.

arXiv:1909.08353•Physical Review Applied•May 18, 2020•12 citations
The generation of non-classical light, especially of single photon states, is mostly limited to non-linear optics in crystals and single emitters. Here we perform research on single organic dye molecules under cryogenic conditions. The molecules are well-behaved and do not blink or bleach. Also they exhibit an enormous brightness (>106 detected counts per second) and have narrow-band emission (<15-20MHz). By atomic sodium vapor we are able to suppress unwanted background emission from residual impurities in the sample. This light is now analyzed for the use in all-optical gates and further quantum optical schemes. A first step is the characterization in a Hong-Ou-Mandel type experiment. Different variations of this are possible – reaching from indistinguishable to distinguishable photons impinging on a beam-splitter.
Single organic dye molecules have been studied for almost three decades. A majority of experiments are now conducted under ambient conditions and aim towards material science and micro-biology. The experiments under cryogenic conditions are often based on highly rigid polycyclic hydrocarbons, which have excellent fluorescing properties when they are operated at temperatures below 2 K. Their photonic advantages integrate their high flux, their narrow-band nature and their tunability over the entire visible spectrum. Therefore the use of organic molecules as efficient and narrow-band single photon sources facilitated a number of quantum optical advances in the past years. The results mostly cover quantum sensing, the formation of quantum hybrid systems and the optical combination of multiple photons in all-optical experiments. Here we present all three fields and outline our own experiments in the combination of single molecule studies, atomic spectroscopy and entanglement generation. The brightness and the narrow-band nature of the molecules are outlined and a delayed-choice quantum eraser is presented. The mode-mixing of two photons on a beam-splitter allows for the generation of a degenerate photon pair, which is resonant to the sodium D2-line. Furthermore, its spectral width matches roughly to the natural linewidth of an isolated sodium atom, such that further experiments are feasible. The entanglement of the post-selected photon pair is testified by a violation of Bell's inequality. Even the raw collected clicks violate Bell's inequality by more than two standard deviations.
Single molecules in solid-state matrices have been proposed as sources of single-photon Fock states back 20 years ago. Their success in quantum optics and in many other research fields stems from the simple recipes used in the preparation of samples, with hundreds of nominally identical and isolated molecules. Main challenges as of today for their application in photonic quantum technologies are the optimization of light extraction and the on-demand emission of indistinguishable photons. We here present Hong-Ou-Mandel experiments with photons emitted by a single molecule of dibenzoterrylene in an anthracene nanocrystal at 3 K, under continuous wave and also pulsed excitation. A detailed theoretical model is applied, which relies on independent measurements for most experimental parameters, hence allowing for an analysis of the different contributions to the two-photon interference visibility, from residual dephasing to spectral filtering.
Single molecules in solid state matrices have been proposed as sources of single photon Fock states back 20 years ago. Their success in quantum optics and in many other research fields stems from the simple recipes used in the preparation of samples, with hundreds of nominally identical and isolated molecules. Main challenges as of today for their application in photonic quantum technologies are the optimization of light extraction and the on-demand emission of indistinguishable photons. We here present Hong–Ou–Mandel (HOM) experiments with photons emitted by a single molecule of dibenzoterrylene in an anthracene nanocrystal at 3 K, under continuous wave and also pulsed excitation. A detailed theoretical model is applied, which relies on independent measurements for most experimental parameters, hence allowing for an analysis of the different contributions to the two-photon interference visibility, from residual dephasing to spectral filtering. A HOM interference visibility of more than 75% is reported, which, according to the model, is limited by the residual dephasing present at the operating temperature.
A single molecule under cryogenic conditions allows one to realize an extremely bright and simultaneously narrow-band single-photon source. We present a review on the different excitation schemes of a single molecule and present the corresponding single-photon nature of the emitted light. Single-molecule spectroscopy has been recently interlinked with atomic spectroscopy. This optical interconnect among the different quantum systems might be enhanced by a so-called Faraday anomalous dispersion optical filter—an ideal tool for many experiments in quantum optics. We introduce our theoretical and experimental approach on these filters which are based on hot atomic sodium vapor. The electrical tunability together with the brightness of a single molecule allows us to record a full atomic spectrum of this filter with the single photons originating from a single-molecular emitter.
A single-photon source is an essential tool for the emerging field of quantum technologies. Ideally, it should be spectrally compatible with other photonic devices while providing a high flux of narrow-band photons. The single organic dye molecule dibenzanthanthrene under cryogenic conditions possesses the given characteristics and therefore constitutes a prominent single-photon source. Nevertheless, the implementation of such a single-photon source requires a complex experimental setup involving a cryostat with a confocal microscope for the effective collection of the molecular emission. In the approach presented here we use a single emitter coupled directly to the end facet of an optical fiber. This has the potential to transfer a single-photon source based on a quantum emitter from a proof-of-principle type of setup to a scalable ``plug-and-play'' device. We present successful coupling of a single organic molecule to an optical fiber and record the excitation spectrum, measure the saturation curve, and analyze the contributions of Raman background fluorescence. The single-photon nature is proven by an antibunched autocorrelation recording, which reveals coherent Rabi oscillations.