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

International Journal of Molecular Sciences

Single Molecule Experiments Challenge the Strict Wave-Particle Dualism of Light

Karl Otto Greulich

Published Jan 21, 2010• 2 citations
Publisher

Abstract

Single molecule techniques improve our understanding of the photon and light. If the single photon double slit experiment is performed at the "single photon limit" of a multi-atom light source, faint light pulses with more than one photon hamper the interpretation. Single molecules, quantum dots or defect centres in crystals should be used as light source. "Single photon detectors" do not meet their promise-only "photon number resolving single photon detectors" do so. Particularly, the accumulation time argument, the only safe basis for the postulate of a strictly particle like photon, has so far not yet been verified.

DOI
10.3390/ijms11010304

Related papers

The Emission of a Single Photon from a Single Atom or Molecule - An Experimenter's View

Karl Otto Greulich

Crucial experiments of physics, such as the quantum mechanical version of the double slit experiment, have so far not been performed with true single (antibunching) photons. Instead, attenuated classical light sources such as bulbs or lasers have been suggested to provide the photons in these experiments. Since attenuators do not change photon statistics, i.e. do not convert classical into non - classical light, reliable single photon beams cannot be generated on this way. Antibunching sources, for example single molecules, are required. Due to the lack of such sources in the past, some extrapolations from the many - photon case to the one photon case have remained speculative, for example the long wavetrain model for a single photon. Alternative hypotheses, elaborated by considering details of the emission of single photons by single molecules are equally probable. Arguments are presented which disfavour the wavetrain model and favour the short pulse as a model for a photon.

Single Molecules•Apr 1, 2002•1 citation

A non-quantum mechanical explanation of the single photon double slit experiment

Karl Otto Greulich

Double slit experiments with true single photons are presently becoming reality. Thus one may speculate that the wave particle duality of light and photons can now be proven unequivocally. This was not the case with earlier experiments using attenuated multi-atom light sources. Here it is suggested that the few available experiments which indeed are using single photons can be explained in a comprehensible manner without invoking quantum mechanics and wave particle dualism. However, one has to give up the notion of an indivisible photon.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Aug 20, 2009•1 citation

Single Photon Light Sources

Karl Otto Greulich, E. Thiel

In the past, generation of single photons for subsequent use in physical or physicochemical experiments was difficult. In the last few years the situation has changed dramatically. Now, such sources based on a number of different techniques are available. Two of them produce antibunching photons by controlled recombination of electrons and holes in semiconductor heterojunctions. A second type of source is based on indium-arsenide quantum dots in high Q factor microcavities. Two further sources use single dibenz-anthanthrene or single terrylene molecules. While all but one sources have to be operated at temperatures close to zero Kelvin, the terrylene source works at room temperature and provides up to 10 billion photons before photodecay, i.e. it can be operated for hours. When the latter is operated at zero Kelvin, it is even more stable and can be used in a microscope to generate complete images. The present review compares and summarizes properties of these single optical photon sources and, in addition, tries to present an argument, why single photons cannot be particle like objects but must have a spatial extension of at least several tens of nanometers.

Single Molecules•Mar 1, 2001•13 citations

Developing a New Quantum Light Source: Single Photons from Single Molecules

Kwang-Geol Lee

In this article, a new kind quantum light source, a single photon source, is introduced.In contrast to other pre-existing light sources, the single photon source enables us to 'get' single photons on demand.This is a truly remarkable

Physics and High Technology•Nov 30, 2013•0 citations

Collecting and Manipulating Single Photons with Near-Unity Efficiency

Stephan Götzinger

In this tutorial I will first review various approaches which have been employed to efficiently collect single photons from a single emitter. In the second part I will discuss experiments where a single molecule provides an optical nonlinearity strong enough to manipulate single photons.

European Conference on Optical Communication•Dec 1, 2020•0 citations

Resolving wave-particle duality could accelerate the mass production of quantum computers

Chandrasekhar Roychoudhuri, Narasimha S. Prasad

Quantum computers, hypothesized in 1980s, use concepts of superposition and entanglement phenomena. Although theoretical propositions and associated search algorithms for accurate measurements are being generated, the development of practical quantum computers themselves are advancing very slowly requiring enormous time and investments. The underlying concepts of a quantum computer are not new to the optical domain. However, the crucial enabling concepts of Entanglement and Superposition Principle are remaining clouded under the unresolved postulates, Wave-Particle Duality (WPD), and Wave Packet Reduction (WPR), implicating incompleteness in the interpretations of the mathematical formalism behind Quantum Mechanics. The WPD debate started during late1600 between Newton and Huygens. Young’s resolution of WPD through his double-slit experiment in 1802 was effectively overturned by Einstein’s interpretation of photoelectric effect as due to “indivisible light quanta”. However, Einstein disowned his “light quanta” postulate shortly before his death in1955, even though it had earned him the Nobel Prize. We resolve WPD by synthesizing Newton’s and Maxwell’s concepts and assume atoms do emit quanta but propagate as time-finite exponential pulses. This assumption also resolves WPR for light-matter interaction with the assumption that Schrodinger’s ψ represents atom’s internal dipolar amplitude stimulations. This over-turns Born’s interpretation that ψ only represents the abstract mathematical probability amplitude, rather than the physical “internal amplitude stimulation” of the quantum entity. However, our concept of atomic pulse emission forces us to re-derive the expression for the N-slit grating-spectrometer response since the classical derivation uses CW light, which does not exist. This pulsespectrometric response function strengthens our postulate since the grating response to the exponential pulse appears to be the convolution of a Lorentzian spectrum with the classical CW response function of the grating. The Fourier Transform of an exponential function is Lorentzian and QM predicts spontaneous emission line width to be Lorentzian. Then, conceptually one can extend the grating-expression (with N=2) to get the double-slit pattern. This approach preserves the classical causality that each of the two slits, like the N-signals out of a grating, are physically real and jointly stimulate the quantum detector array at the far field to generate the “Local” cosine fringes. The detector array executes the square modulus operation on its imposed dipolar amplitude stimulation and absorbs the necessary energy to fill up their quantum cups. Hence the double-slit pattern must also be “Local”, just as the N-slit grating spectrum is generated locally at the exit spectral-plane of the spectrometer. This removes the need to believe that “single photons” mysteriously generate the double slit pattern.

Quantum Computing, Communication, and Simulation•Mar 12, 2024•2 citations
Single molecule techniques improve our understanding of the photon and light. If the single photon double slit experiment is performed at the "single photon limit" of a multi-atom light source, faint light pulses with more than one photon hamper the interpretation. Single molecules, quantum dots or defect centres in crystals should be used as light source. "Single photon detectors" do not meet their promise-only "photon number resolving single photon detectors" do so. Particularly, the accumulation time argument, the only safe basis for the postulate of a strictly particle like photon, has so far not yet been verified.
Crucial experiments of physics, such as the quantum mechanical version of the double slit experiment, have so far not been performed with true single (antibunching) photons. Instead, attenuated classical light sources such as bulbs or lasers have been suggested to provide the photons in these experiments. Since attenuators do not change photon statistics, i.e. do not convert classical into non - classical light, reliable single photon beams cannot be generated on this way. Antibunching sources, for example single molecules, are required. Due to the lack of such sources in the past, some extrapolations from the many - photon case to the one photon case have remained speculative, for example the long wavetrain model for a single photon. Alternative hypotheses, elaborated by considering details of the emission of single photons by single molecules are equally probable. Arguments are presented which disfavour the wavetrain model and favour the short pulse as a model for a photon.
Double slit experiments with true single photons are presently becoming reality. Thus one may speculate that the wave particle duality of light and photons can now be proven unequivocally. This was not the case with earlier experiments using attenuated multi-atom light sources. Here it is suggested that the few available experiments which indeed are using single photons can be explained in a comprehensible manner without invoking quantum mechanics and wave particle dualism. However, one has to give up the notion of an indivisible photon.
In the past, generation of single photons for subsequent use in physical or physicochemical experiments was difficult. In the last few years the situation has changed dramatically. Now, such sources based on a number of different techniques are available. Two of them produce antibunching photons by controlled recombination of electrons and holes in semiconductor heterojunctions. A second type of source is based on indium-arsenide quantum dots in high Q factor microcavities. Two further sources use single dibenz-anthanthrene or single terrylene molecules. While all but one sources have to be operated at temperatures close to zero Kelvin, the terrylene source works at room temperature and provides up to 10 billion photons before photodecay, i.e. it can be operated for hours. When the latter is operated at zero Kelvin, it is even more stable and can be used in a microscope to generate complete images. The present review compares and summarizes properties of these single optical photon sources and, in addition, tries to present an argument, why single photons cannot be particle like objects but must have a spatial extension of at least several tens of nanometers.
Quantum computers, hypothesized in 1980s, use concepts of superposition and entanglement phenomena. Although theoretical propositions and associated search algorithms for accurate measurements are being generated, the development of practical quantum computers themselves are advancing very slowly requiring enormous time and investments. The underlying concepts of a quantum computer are not new to the optical domain. However, the crucial enabling concepts of Entanglement and Superposition Principle are remaining clouded under the unresolved postulates, Wave-Particle Duality (WPD), and Wave Packet Reduction (WPR), implicating incompleteness in the interpretations of the mathematical formalism behind Quantum Mechanics. The WPD debate started during late1600 between Newton and Huygens. Young’s resolution of WPD through his double-slit experiment in 1802 was effectively overturned by Einstein’s interpretation of photoelectric effect as due to “indivisible light quanta”. However, Einstein disowned his “light quanta” postulate shortly before his death in1955, even though it had earned him the Nobel Prize. We resolve WPD by synthesizing Newton’s and Maxwell’s concepts and assume atoms do emit quanta but propagate as time-finite exponential pulses. This assumption also resolves WPR for light-matter interaction with the assumption that Schrodinger’s ψ represents atom’s internal dipolar amplitude stimulations. This over-turns Born’s interpretation that ψ only represents the abstract mathematical probability amplitude, rather than the physical “internal amplitude stimulation” of the quantum entity. However, our concept of atomic pulse emission forces us to re-derive the expression for the N-slit grating-spectrometer response since the classical derivation uses CW light, which does not exist. This pulsespectrometric response function strengthens our postulate since the grating response to the exponential pulse appears to be the convolution of a Lorentzian spectrum with the classical CW response function of the grating. The Fourier Transform of an exponential function is Lorentzian and QM predicts spontaneous emission line width to be Lorentzian. Then, conceptually one can extend the grating-expression (with N=2) to get the double-slit pattern. This approach preserves the classical causality that each of the two slits, like the N-signals out of a grating, are physically real and jointly stimulate the quantum detector array at the far field to generate the “Local” cosine fringes. The detector array executes the square modulus operation on its imposed dipolar amplitude stimulation and absorbs the necessary energy to fill up their quantum cups. Hence the double-slit pattern must also be “Local”, just as the N-slit grating spectrum is generated locally at the exit spectral-plane of the spectrometer. This removes the need to believe that “single photons” mysteriously generate the double slit pattern.