1,721,191 research outputs found
Development of silicon carbide photonics for quantum technologies
No full textQuantum information sciences offer novel capabilities in the fields of computation, data security and sensing. In order to deliver these improvements, information needs to be encoded in a physical quantum system the realization of which is technologically challenging. Even though several platforms have been proposed for computation, quantum information encoded in nonclassical states of light is going to play a central role since the classical fiber technology already provides an almost ideal transmitting medium. Furthermore, a hybrid approach formed together with solid state emitters could meet the non-trivial requirement needed for quantum computation. In the past ten years, efforts have been placed in integrating the bulky optical components required to manipulate nonclassical states of light, giving birth to the field of quantum photonics. Between all the different materials proposed, 3C silicon carbide (SiC) meets all the complex requirements needed for photonic quantum technologies and the development of essential components to this scope is the main subject of this thesis. The design, fabrication and characterization of small modal area waveguides, grating couplers and ring resonators made in SiC are reported. Four wave mixing was demonstrated thanks to the small modal volume achieved in the ring resonator and the Kerr coefficient of SiC was retrieved. The realization of photonic crystal cavities is also investigated with the aim to harness quantum emitters. Thanks to the demonstration of coupling between confined and propagating surface waves, SiC is a potential platform for quantum applications in the mid-infrared. Finally, the generation of photon pairs in the near-infrared by means of third order nonlinear process is reported using ring resonators fabricated in silicon nitride
Linear Integrated Optics in 3C Silicon Carbide
No full textDataset for the paper Linear Integrated Optics in 3C Silicon Carbide</span
Dataset for “Four wave mixing in 3C SiC ring resonators”
No full textDataset supports:
Politi, A., & Martini, F. (2018). Four wave mixing in 3C SiC Ring Resonators. Applied Physics Letters.</span
Entanglement, Einstein Podolsky Rosen correlations and Schrodinger cat state generation by quantum-injected optical parametric amplification
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Non-linear parametric processes in quantum information
No full textIn recent years, a large number of experiments aimed at the veritication of fundamental aspects of quantum mechanics, such as the Bell's inequality test of quantum nonlocality, have been realized by adopting photon particles mutually interacting according the celebrated methods of non-linear optics (NLO). In addition, the sophisticated NLO methods have been extended to relevant investigations and realizations in the domain of the emerging new sciences Of Quantum Information (QI) and Quantum Communication. Indeed NLO has proved to be an excellent theoretical and experimental test bench for the novel concepts introduced by QI The present work is intended to survey the most relevant quantum processes investigated by NLO by focusing on the generation and on the manipulation of entangled NL photon states by the three-wave NL parametric processes. (c) 2005 Published by Elsevier Ltd
Optimal quantum machines by linear and non-linear optics
No full textSince manipulations of qubits are constrained by the quantum mechanical rules, several classical information tasks can not be perfectly extended to the quantum world. The more relevant limitations in quantum information processing are the impossibility to perfectly clone any unknown qubit and to map it in its orthogonal state. Even if these two processes are unrealizable in their exact forms, they can be optimally approximated by the so-called universal quantum machines: the optimal quantum cloning machine (UOQCM) and the universal-NOT (U-NOT) gate. Investigation of these optimal transformations is important since it reveals bounds on optimal manipulations of information with quantum systems. The 1->1 U-NOT gate and the 1->2 UOQCM have been experimentally demonstrated by adopting the process of stimulated emission into an optical parametric amplifier and by slightly modifying the quantum state teleportation protocol. © 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Violation of the Bell Inequalities by Weyl Conformal Quantum Geometrodynamics<BR> A Re-Interpretation of Quantum Nonlocality
No full textThe principles and methods of the Conformal Quantum Geometrodynamics (CQG) based on the Weyl differential geometry are presented. The theory, applied to the case of the relativistic single quantum spin 1/2 leads to a novel and unconventional derivation of Dirac's equation. The extension of the theory to the case of two spins 1/2 in EPR entangled state and to the related violation of Bell's inequalities leads, by an exact non relativistic analysis, to an insightful resolution of all paradoxes implied by quantum nonlocality, which is re-interpreted as a peculiar quantum correlation mechanism mediated by the Weyl's curvature. All this consists of a realistic interpretation of quantum nonlocality in terms of the geometrical structure supporting the dynamics of fields and particles
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