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

physica status solidi (b)

Indistinguishable single photons from a quantum dot

David A. Fattal, Charles Santori, Jelena Vuckovic A, Glenn S. Solomon, Y. Yamamoto

Published Jul 1, 2003• 4 citations
Publisher

Abstract

Abstract We report a set of experiments designed to test the quantum indistinguishability of single photons emitted by a resonantly pumped InAs/GaAs quantum dot, embedded in a microcavity. We first performed high resolution interferometric measurements on the source to infer its coherence time. By comparison with the exciton lifetime, obtained by time‐resolved spectroscopy, we found that some quantum dots were emitting almost transform‐limited photons. The measured ratio of the coherence time to the pulse duration gives a lower bound on the dephasing time which agrees well with previous studies. We then directly measured the mean overlap between wave packets of consecutive photons emitted 2 ns apart, through a Hong–Ou–Mandel type two‐photon interference experiment. For the best dot, an overlap as high as 0.81 was inferred. This result suggests that quantum dots could be a practical single photon source to perform quantum information processing experiments. We stress the importance of the microcavity for identical photon generation.

DOI
10.1002/pssb.200303050

Related papers

Indistinguishable single photons from a single quantum dot microcavity

Charles Santori, David A. Fattal, Jelena Vuckovic A +2 more

A single-photon device based on a semiconductor quantum dot embedded in an optical microcavity is described. The spontaneous emission lifetime, multi-photon suppression, and spectral linewidth are measured. It is then shown that consecutively emitted photons possess a large degree of quantum-mechanical indistinguishability, with a mean wave-packet overlap as large as 0.8. This demonstration is accomplished through a Hong-Ou-Mandel-type two-photon interference experiment.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Jun 25, 2003•1 citation

Quantum dot single photon sources

Y. Yamamoto

Summary form only given. Single-photon sources have recently been demonstrated using a variety of devices, including molecules, mesoscopic quantum wells, colour centers, trapped ions, and semiconductor quantum dots. These sources rarely emit two or more photons in the same pulse, compared to a Poisson-distributed source of the same intensity. Numerous applications for single-photon sources have been proposed in the field of quantum information. However, most, including linear-optical quantum computation, also require that consecutive photons have identical wave packets. For a source based on a single quantum emitter, the emitter must therefore be excited in a rapid or deterministic way, and interact little with its surrounding environment. Here, we test the indistinguishability of photons emitted by a semiconductor quantum dot in a microcavity through a Hong-Ou-Mandel-type two-photon interference experiment. We find that consecutive photons are largely indistinguishable, with a mean wave-packet overlap as large as 0.81, making this source useful in a variety of experiments in quantum optics and quantum information.

European Quantum Electronics Conference (EQEC)•Jan 1, 2003•0 citations

Highly indistinguishable photons from a quantum dot in a microcavity

Stefanie Weiler, Ata Ulhaq, Sven M. Ulrich +4 more

Abstract We investigated the indistinguishability of photons emitted by single self‐assembled (In,Ga)As/GaAs quantum dots (QDs) coupled to the fundamental mode (FM) of a pillar microcavity. By systematic pre‐characterization, optimum conditions with respect to fast radiative decay (Purcell enhancement), long coherence time, and close to background‐free single‐photon emission have been derived. For different spectral detunings between QD and FM emission, Hong‐Ou‐Mandel‐type (HOM) two‐photon interference has been measured as a function of temporal photon wavepacket overlap. Detailed analysis of our data (under consideration of setup limitations) anticipates the generation of highly indistinguishable photons with up to VHOM = 0.82 visibility.

physica status solidi (b)•Dec 22, 2010•12 citations

Indistinguishable single photons generated by a quantum dot under resonant excitation observable without postselection

Léonard Monniello, Antoine Reigue, Richard Hostein +4 more

We report on two-photon interference of highly indistinguishable single photons emitted by a quantum dot. Strictly resonant excitation with picosecond laser pulses has been used to prepare coherent states with a significantly increased coherence time $({T}_{2}\ensuremath{\sim}1\text{ns})$ and reduced lifetime $({T}_{1}\ensuremath{\sim}650\text{ps})$, as compared to a nonresonant excitation scheme. Indistinguishable photons, with visibilities greater than 70%, have been observed by measuring the Hong-Ou-Mandel dip without postselection of the interfering photons. Near-unity indistinguishable photons should be achievable by preventing fluctuations in the electrostatic environment in the vicinity of the dots, considered as an important source of decoherence.

Physical Review B•Jul 21, 2014•27 citations

Quantum dots as single-photon sources for quantum information processing

D. C. Unitt, Anthony J. Bennett, P. Atkinson +7 more

Semiconductor pillar microcavities containing quantum dots have shown promise as efficient sources of single and correlated pairs of photons, which may find applications in quantum information processing. In this paper we discuss the use of these sources to generate single photons and the use of pillars with elliptical cross-section to enhance and select a particular photon state. Single-photon interference measurements are also performed and show coherence times of up to 180 ps for quasi-resonantly pumped dots. Hong–Ou–Mandel-type two-photon interference measurements using a fibre interferometer indicate that individually created photons display a large degree of indistinguishability.

Journal of Optics B Quantum and Semiclassical Optics•Jun 30, 2005•27 citations

Resonant emission of single quantum dots: towards an ultra-coherent single photon source

Hai Son Nguyen, Gregory C. Sallen, Christophe Voisin +3 more

Single photon emission is one of the most striking optical properties of semiconductor quantum dots (QDs), and the corresponding photon anti-bunching effect was observed by non-resonant and resonant photoluminescence experiments in single QDs [1,2,3,4]. Other experiments demonstrated the possibility to use single QDs for the generation of indistinguishable single photons [3]. An important general issue is to reach the so-called fundamental radiative limit. Several strategies have been followed in that sense such as the shortening of population lifetime induced by the Purcell effect [5] or the reduction of pure dephasing by resonant excitation [2,3,4]. Up to now, all the measurements reported in the literature focus on the incoherent photoluminescence signal for achieving single photon emission. In this regime, the linewidth of the photoluminescence spectrum is always limited to the radiative limit. In this paper, we report on the resonant emission (RE) of the exciton in single InAs/GaAs QDs embedded in a planar microcavity, in an orthogonal excitation-detection geometry [4]. We present an original type of single photon source based on the coherent laser light scattering by a single QD [6]. Besides the antibunching effect showing the non-classical nature of the emitted light, we observe that the QD emission spectrum is determined by the spectrum of the resonant excitation laser. We present high-resolution measurements by Fourier transform spectroscopy of the RE where the data are fitted to the first-order correlation function g(1)(τ) of the RE of a two-level system. The inverse Fourier transform of the g(1)(τ) function allows a direct comparison of the different RE emission profiles. We show that, by reducing the resonant excitation power, the so-called Mollow triplet shrinks to a single narrow Lorentzian line, while the relative intensity of this narrow peak increases and tends to overwhelm the RE spectrum. This implies that single QDs can produce single photons with a coherence time that is not limited anymore by the QD electronic properties, resulting in an ultra-coherent character [6]. In conclusion, the resulting " ultra-coherent single photon source " promises high degrees of indistinguishability of the emitted photons which is a crucial requirement for quantum information applications. [1] P. Michler et al., Science 290, 2282 (2000). [2] A. Muller et al., Phys. Rev. Lett. 99, 187402 (2007). [3] S. Ates et al., Phys. Rev. Lett. 103, 167402 (2009). [4] H. S. Nguyen et al., Phys. Rev. Lett. 108, 057401 (2012). [5] C. Santori et al., Nature 419, 594 (2002). [6] H. S. Nguyen et al., Appl. Phys. Lett. 99, 261904 (2011).

•Jul 29, 2012•0 citations
Abstract We report a set of experiments designed to test the quantum indistinguishability of single photons emitted by a resonantly pumped InAs/GaAs quantum dot, embedded in a microcavity. We first performed high resolution interferometric measurements on the source to infer its coherence time. By comparison with the exciton lifetime, obtained by time‐resolved spectroscopy, we found that some quantum dots were emitting almost transform‐limited photons. The measured ratio of the coherence time to the pulse duration gives a lower bound on the dephasing time which agrees well with previous studies. We then directly measured the mean overlap between wave packets of consecutive photons emitted 2 ns apart, through a Hong–Ou–Mandel type two‐photon interference experiment. For the best dot, an overlap as high as 0.81 was inferred. This result suggests that quantum dots could be a practical single photon source to perform quantum information processing experiments. We stress the importance of the microcavity for identical photon generation.
Summary form only given. Single-photon sources have recently been demonstrated using a variety of devices, including molecules, mesoscopic quantum wells, colour centers, trapped ions, and semiconductor quantum dots. These sources rarely emit two or more photons in the same pulse, compared to a Poisson-distributed source of the same intensity. Numerous applications for single-photon sources have been proposed in the field of quantum information. However, most, including linear-optical quantum computation, also require that consecutive photons have identical wave packets. For a source based on a single quantum emitter, the emitter must therefore be excited in a rapid or deterministic way, and interact little with its surrounding environment. Here, we test the indistinguishability of photons emitted by a semiconductor quantum dot in a microcavity through a Hong-Ou-Mandel-type two-photon interference experiment. We find that consecutive photons are largely indistinguishable, with a mean wave-packet overlap as large as 0.81, making this source useful in a variety of experiments in quantum optics and quantum information.
Abstract We investigated the indistinguishability of photons emitted by single self‐assembled (In,Ga)As/GaAs quantum dots (QDs) coupled to the fundamental mode (FM) of a pillar microcavity. By systematic pre‐characterization, optimum conditions with respect to fast radiative decay (Purcell enhancement), long coherence time, and close to background‐free single‐photon emission have been derived. For different spectral detunings between QD and FM emission, Hong‐Ou‐Mandel‐type (HOM) two‐photon interference has been measured as a function of temporal photon wavepacket overlap. Detailed analysis of our data (under consideration of setup limitations) anticipates the generation of highly indistinguishable photons with up to VHOM = 0.82 visibility.
We report on two-photon interference of highly indistinguishable single photons emitted by a quantum dot. Strictly resonant excitation with picosecond laser pulses has been used to prepare coherent states with a significantly increased coherence time $({T}_{2}\ensuremath{\sim}1\text{ns})$ and reduced lifetime $({T}_{1}\ensuremath{\sim}650\text{ps})$, as compared to a nonresonant excitation scheme. Indistinguishable photons, with visibilities greater than 70%, have been observed by measuring the Hong-Ou-Mandel dip without postselection of the interfering photons. Near-unity indistinguishable photons should be achievable by preventing fluctuations in the electrostatic environment in the vicinity of the dots, considered as an important source of decoherence.
Semiconductor pillar microcavities containing quantum dots have shown promise as efficient sources of single and correlated pairs of photons, which may find applications in quantum information processing. In this paper we discuss the use of these sources to generate single photons and the use of pillars with elliptical cross-section to enhance and select a particular photon state. Single-photon interference measurements are also performed and show coherence times of up to 180 ps for quasi-resonantly pumped dots. Hong–Ou–Mandel-type two-photon interference measurements using a fibre interferometer indicate that individually created photons display a large degree of indistinguishability.
Single photon emission is one of the most striking optical properties of semiconductor quantum dots (QDs), and the corresponding photon anti-bunching effect was observed by non-resonant and resonant photoluminescence experiments in single QDs [1,2,3,4]. Other experiments demonstrated the possibility to use single QDs for the generation of indistinguishable single photons [3]. An important general issue is to reach the so-called fundamental radiative limit. Several strategies have been followed in that sense such as the shortening of population lifetime induced by the Purcell effect [5] or the reduction of pure dephasing by resonant excitation [2,3,4]. Up to now, all the measurements reported in the literature focus on the incoherent photoluminescence signal for achieving single photon emission. In this regime, the linewidth of the photoluminescence spectrum is always limited to the radiative limit. In this paper, we report on the resonant emission (RE) of the exciton in single InAs/GaAs QDs embedded in a planar microcavity, in an orthogonal excitation-detection geometry [4]. We present an original type of single photon source based on the coherent laser light scattering by a single QD [6]. Besides the antibunching effect showing the non-classical nature of the emitted light, we observe that the QD emission spectrum is determined by the spectrum of the resonant excitation laser. We present high-resolution measurements by Fourier transform spectroscopy of the RE where the data are fitted to the first-order correlation function g(1)(τ) of the RE of a two-level system. The inverse Fourier transform of the g(1)(τ) function allows a direct comparison of the different RE emission profiles. We show that, by reducing the resonant excitation power, the so-called Mollow triplet shrinks to a single narrow Lorentzian line, while the relative intensity of this narrow peak increases and tends to overwhelm the RE spectrum. This implies that single QDs can produce single photons with a coherence time that is not limited anymore by the QD electronic properties, resulting in an ultra-coherent character [6]. In conclusion, the resulting " ultra-coherent single photon source " promises high degrees of indistinguishability of the emitted photons which is a crucial requirement for quantum information applications. [1] P. Michler et al., Science 290, 2282 (2000). [2] A. Muller et al., Phys. Rev. Lett. 99, 187402 (2007). [3] S. Ates et al., Phys. Rev. Lett. 103, 167402 (2009). [4] H. S. Nguyen et al., Phys. Rev. Lett. 108, 057401 (2012). [5] C. Santori et al., Nature 419, 594 (2002). [6] H. S. Nguyen et al., Appl. Phys. Lett. 99, 261904 (2011).