## Session Overview |

## Quantum light-matter interactions: sensing, communications, and information processing - 5Virtual room: COPL - 5 |

Wednesday, May 27 |

16:22 |
QT-5-27-1 / Black Holes, Quantum Optics, and Quantum Metrology
Invited Speaker* Jeff S. Lundeen, University of Ottawa, Canada
I will introduce the connection between the spontaneous generation of photon pairs in nonlinear optical media and the creation of particle-antiparticle pairs around black holes, i.e., Hawking radiation. In standard modelling, both processes use the Â“parametric approximation,Â” in which the pump is taken to be a classical field. Other groups have proposed that the removal of this approximation could resolve the infamous black hole information paradox, which I will also introduce. In order to gain insight into the consequences of this removal, we theoretically and experimentally investigate situations in quantum optics in which it matters that the pump is actually a quantum field, even if it is, say, a laser pulse. For example, we created a fully-quantum theoretical model of a nonlinear interferometer that is central to quantum metrology. This model revealed that the interferometer produces three-field entanglement and, consequently, does not reach the fundamental limit of phase-sensitivity, in contrast to past claims. On the experimental side, I will present the generation of high-gain spontaneous parametric down-conversion with record-high efficiency. Remarkably, we observe that every third photon in a pump pulse is downconverted to a photon pair. We show that the process radically alters the photon-number statistics of the pump field. This is a signature that information is flowing out of the photon pair fields and back into the pump, as would be needed to resolve the black hole information paradox. |

16:49 |
QT-5-27-2 / Hybrid quantum networks based on trapped ions and neutral atoms
Invited Speaker* Qudsia Quraishi, University of Maryland, Army Research Laboratory, United States
Practical implementation of quantum networks will require integration of hybrid components. Trapped ions and neutrals atoms networked together form an excellent platform for leveraging the advantages of each system. |

17:16 |
QT-5-27-3 / Near-Term Photonic Quantum Computing on the Cloud
Invited Speaker* Zach Vernon, Xanadu, Canada
TBA |

17:43 |
QT-5-27-4 / Quantum dot as a single photon source for satellite-based quantum key distribution
* Poompong Chaiwongkhot, University of Waterloo, Canada
Sara Hosseini, University of Waterloo Arash Ahmadi, University of Waterloo Brendon Higgins, University of Waterloo Michael E. Reimer, University of Waterloo Thiomas Jennewein, University of Waterloo The development of quantum dot as a single-photon source is progressed rapidly. Recent results show that this system could generate single photon pulse with high frequency and quality. This could be used in a BB84 QKD system which, with near-perfect single photon source, has much lower post processing cost than the widely used decoy-state protocol. This would be an answer to a major challenge for satellite based QKD which is operating under high channel loss condition and limited key exchange time windows. This study compares practical key generation rate between conventional decoy state BB84 quantum key distribution and QKD with quantum dots as single photon source. We uses realistic parameters for satellite QKD as well as finite-size effect to experimentally study the performance of the two QKD system. The result shows that a BB84 quantum dot QKD could outperform a decoy-state QKD system using the same photon repetition rate as the excitation rate of the quantum dot |

18:00 |
QT-5-27-5 / Full-Field Imaging With Quantum Illumination
* Thomas Gregory, University of Glasgow, United Kingdom
Paul-Antoine Moreau, University of Glasgow Ermes Toninelli, University of Glasgow Miles Padgett, University of Glasgow We present a full-field quantum imaging scheme using a quantum illumination protocol that exploits the spatial correlations between entangled photon-pairs. In doing so we exhibit an advantage for this scheme over the corresponding classical scheme in the presence of increasing levels of noise and loss. |

18:16 |
QT-5-27-6 / Estimation of the thickness of a crystal using superresolution ghost-imaging
Express presentation
* Florence Grenapin, University of Ottawa, Canada
Dilip Paneru, University of Ottawa Yingwen Zhang, University of Ottawa Ebrahim Karimi, University of Ottawa Frederic Bouchard, University of Ottawa Abstract—In all direct imaging systems, the maximal attainable resolution between two distant point sources is limited by the Rayleigh criterion. Recent works have shown that taking the phase information of the EM field into account, allows us to surpass the Rayleigh limit and super resolve the separation between two incoherent point sources. Here we merge the idea of superresolution with ghost-imaging- a technique that exploits the spatial correlations of light, to estimate the thickness of a birefringent calcite crystal. To this end, we project the light in one of the phase sensitive modes (e.g. Hermite Gauss modes) using a Spatial Light Modulator. |

18:21 |
QT-5-27-7 / Herriott cells as image-preserving delay lines
Express presentation
Boris Braverman, University of Ottawa * Katherine Bearne, University of Ottawa, Canada
Robert W. Boyd, University of Ottawa Many quantum imaging experiments rely on the spatial and temporal correlations between two entangled photons, one of which (the “herald”) triggers the detection of the “signal” photon, which has interacted with the system of interest. This procedure often requires a delay line for the signal photon, which is generally quite space-consuming. As a solution to this, we experimentally investigate the potential for a Herriott cell to be used as an image-preserving delay line. |