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Sub-Poissonian Statistics and Quantum Non-Gaussianity from High-Harmonic Generation
Authors:
David Theidel,
Mackrine Nahra,
Ilya Karuseichyk,
Houssna Griguer,
Mateusz Weis,
Viviane Cotte,
Hamed Merdji
Abstract:
Quantum technologies are powered by platforms to generate complex non-classical states of matter or light to realize applications. We investigate the non-classical properties of high-harmonic generation in semiconductors, an emerging photonic platform. Measuring the click statistics of three double-digit orders, we evaluate witness operators to certify the non-classicality of the generated states.…
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Quantum technologies are powered by platforms to generate complex non-classical states of matter or light to realize applications. We investigate the non-classical properties of high-harmonic generation in semiconductors, an emerging photonic platform. Measuring the click statistics of three double-digit orders, we evaluate witness operators to certify the non-classicality of the generated states. We show that higher-order harmonics driven by a coherent laser are squeezed and entangled. The properties of the emission are well retrieved with an entangled Gaussian state model, obtained by numerical state optimization to multiple observables. Additionally, we perform inter-order heralded measurements to engineer the quantum state of the emission. The heralded states have distinct properties, showing sub-Poissonian photon statistics. Further, we witness the generation of a quantum non-Gaussian state, a resource highly relevant for quantum information. With this, we establish high-harmonic generation as a platform for generating quantum optical resources.
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Submitted 13 June, 2026; v1 submitted 11 February, 2026;
originally announced February 2026.
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Single germanium vacancy centres in nanodiamonds with bulk-like spectral stability
Authors:
Mackrine Nahra,
Daniel Alshamaa,
Regis Deturche,
Valery Davydov,
Ludmila Kulikova,
Viatcheslav Agafonov,
Christophe Couteau
Abstract:
Motivated by the success of group IV colour centres in nanodiamonds (NDs) for hybrid technology requiring a single photon source, we study single germanium-vacancy (GeV$^-$) centres in NDs at room temperature with size rangingfrom 10 to 50 nm and with remarkable spectral properties. We characterize their zero-phonon line (ZPL), study their internal population dynamics and compare their emission pr…
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Motivated by the success of group IV colour centres in nanodiamonds (NDs) for hybrid technology requiring a single photon source, we study single germanium-vacancy (GeV$^-$) centres in NDs at room temperature with size rangingfrom 10 to 50 nm and with remarkable spectral properties. We characterize their zero-phonon line (ZPL), study their internal population dynamics and compare their emission properties in the framework of a three level model with intensity dependent de-shelving. Furthermore, we characterize their lifetime, polarization and brightness. We find amaximum photon emission count rate of 1.6 MHz at saturation. We also report a polarization visibility of 92% from the fluorescence light, which potentially makes GeV$^-$ centres good candidates for quantum key distribution (QKD)requiring polarized single photons. We show that the GeV$^-$ in NDs presented in this work have a comparable spectral stability compared to their bulk counterpart which is needed for future applications using NDs.
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Submitted 29 October, 2020;
originally announced October 2020.
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Hybrid plasmonic nano-emitters with controlled single quantum emitter positioning on the local excitation field
Authors:
Dandan Ge,
Sylvie Marguet,
Ali Issa,
Safi Jradi,
Tien Hoa Nguyen,
Mackrine Nahra,
Jéremie Béal,
Régis Deturche,
Hongshi Chen,
Sylvain Blaize,
Jérôme Plain,
Céline Fiorini,
Ludovic Douillard,
Olivier Soppera,
Xuan Quyen Dinh,
Cuong Dang,
Xuyong Yang,
Tao Xu,
Bin Wei,
Xiao Wei Sun,
Christophe Couteau,
Renaud Bachelot
Abstract:
Hybrid plasmonic nanoemitters based on the combination of quantum dot emitters (QD) and plasmonic nanoantennas open up new perspectives in the control of light. However, precise positioning of any active medium at the nanoscale constitutes a challenge. Here, we report on the optimal overlap of antenna's near-field and active medium whose spatial distribution is controlled via a plasmon-triggered 2…
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Hybrid plasmonic nanoemitters based on the combination of quantum dot emitters (QD) and plasmonic nanoantennas open up new perspectives in the control of light. However, precise positioning of any active medium at the nanoscale constitutes a challenge. Here, we report on the optimal overlap of antenna's near-field and active medium whose spatial distribution is controlled via a plasmon-triggered 2-photon polymerization of a photosensitive formulation containing QDs. Au nanoparticles of various geometries are considered. The response of these hybrid nano-emitters is shown to be highly sensitive to the light polarization. Different light emission states are evidenced by photoluminescence measurements. These states correspond to polarization-sensitive nanoscale overlap between the exciting local field and the active medium distribution. The decrease of the QD concentration within the monomer formulation allows trapping of a single quantum dot in the vicinity of the Au particle. The latter objects show polarization-dependent switching in the single-photon regime.
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Submitted 15 July, 2020;
originally announced July 2020.
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Nanophotonic approaches for integrated quantum photonics
Authors:
Stefano Pierini,
Mackrine Nahra,
Maxime Joos,
Muhammad H. Muhammad,
Viatcheslav Agafonov,
Emmanuel Lhuillier,
Fabien Geoffray,
Valery Davydov,
Quentin Glorieux,
Elisabeth Giacobino,
Sylvain Blaize,
Alberto Bramati,
Christophe Couteau
Abstract:
Photons for quantum technologies have been identified early on as a very good candidate for carrying quantum information encoded onto them, either by polarization encoding, time encoding or spatial encoding. Quantum cryptography, quantum communications, quantum networks in general and quantum computing are some of the applications targeted by what is now called quantum photonics. Nevertheless, it…
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Photons for quantum technologies have been identified early on as a very good candidate for carrying quantum information encoded onto them, either by polarization encoding, time encoding or spatial encoding. Quantum cryptography, quantum communications, quantum networks in general and quantum computing are some of the applications targeted by what is now called quantum photonics. Nevertheless, it was pretty clear at an early stage that bulk optics for handling quantum states of light with photons would not be able to deliver what is needed for these technologies. More recently, single photons, entangled photons and quantum optics in general have been coupled to more integrated approaches coming from classical optics in order to meet the requirements of scalability, reliablility and efficiency for quantum technologies. In this article, we develop our recent advances in two different nanophotonic platforms for quantum photonics using elongated optical fibers and integrated glass waveguides made by the so-called ion-exchange technique. We also present our latest results on quantum nanoemitters that we plan to couple and incorporate with our photonics platforms. These nanoemitters are of two kinds: nanocrystals made of perovskites as well as silicon-vacancy defect centers in nanodiamonds. Some of their properties are developed in this work. We will then give the general steps necessary in order to couple these nanoemitters efficiently with our platforms in the near future.
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Submitted 23 September, 2019;
originally announced September 2019.