Introduction to generation, manipulation and characterization of optical quantum states

• URL: http://arxiv.org/abs/2107.02519v2
• Date: Mon, 20 Sep 2021 11:51:39 GMT
• Title: Introduction to generation, manipulation and characterization of optical quantum states
• Authors: Stefano Olivares
• Abstract summary: This tutorial provides the theoretical tools needed to describe optical quantum states. We introduce the concept of operator ordering and the description of a system by means of the $p$-ordered characteristic functions. Finally, we introduce the balanced homodyne detection to measure the quadrature operator and the homodyne tomography as a tool for characterizing quantum optical states.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Why do we need quantization to describe vision? What are the quadrature operators of the electromagnetic field? Is it possible to measure them? What are the characteristic functions useful for? In this brief tutorial we provide the theoretical tools needed to describe the generation, manipulation and characterization of optical quantum states and of the main passive (beam splitters) and active (squeezers) devices involved in experiments, such as the Hong-Ou-Mandel interferometer and the continuous-variable quantum teleportation. We also introduce the concept of operator ordering and the description of a system by means of the $p$-ordered characteristic functions. Then we focus on the quasi-probability distributions and, in particular, on the relation between the marginals of the Wigner function and the outcomes of the quadrature operator measurement. Finally, we introduce the balanced homodyne detection to measure the quadrature operator and the homodyne tomography as a tool for characterizing quantum optical states also in the presence of non-unit quantum efficiency.

Related papers

• Wigner Function of Observed Quantum Systems [0.0]
  Wigner function was introduced as an attempt to describe quantum mechanical fields with the tools inherited from classical statistical mechanics. I show that the Wigner function can still expose the quantumness of the radiation field, even if the detection has finite spectral resolution.
  arXiv  Detail & Related papers  (2025-01-07T15:49:01Z)
• Towards quantum computing Feynman diagrams in hybrid qubit-oscillator devices [0.0]
  We show that experiments in hybrid qubit-oscillator devices can be seen through the lens of functional calculus and path integrals. This connection suggests an expansion of the characteristic function in terms of Feynman diagrams. We discuss how these ideas can be generalized to finite temperatures via the Schwinger-Keldysh formalism.
  arXiv  Detail & Related papers  (2024-11-07T19:17:00Z)
• Hysteresis and Self-Oscillations in an Artificial Memristive Quantum Neuron [79.16635054977068]
  We study an artificial neuron circuit containing a quantum memristor in the presence of relaxation and dephasing. We demonstrate that this physical principle enables hysteretic behavior of the current-voltage characteristics of the quantum device.
  arXiv  Detail & Related papers  (2024-05-01T16:47:23Z)
• Measurement-induced entanglement and teleportation on a noisy quantum processor [105.44548669906976]
  We investigate measurement-induced quantum information phases on up to 70 superconducting qubits. We use a duality mapping, to avoid mid-circuit measurement and access different manifestations of the underlying phases. Our work demonstrates an approach to realize measurement-induced physics at scales that are at the limits of current NISQ processors.
  arXiv  Detail & Related papers  (2023-03-08T18:41:53Z)
• Deterministic Free-Propagating Photonic Qubits with Negative Wigner Functions [0.0]
  Coherent states ubiquitous in classical and quantum communications, squeezed states used in quantum sensing, and even highly-entangled states studied in the context of quantum computing can be produced deterministically. We describe the first fully deterministic preparation of non-Gaussian Wigner-negative states of light, obtained by mapping the internal state of an intracavdberg superatom onto an optical qubit.
  arXiv  Detail & Related papers  (2022-09-05T16:37:42Z)
• Noisy Quantum Kernel Machines [58.09028887465797]
  An emerging class of quantum learning machines is that based on the paradigm of quantum kernels. We study how dissipation and decoherence affect their performance. We show that decoherence and dissipation can be seen as an implicit regularization for the quantum kernel machines.
  arXiv  Detail & Related papers  (2022-04-26T09:52:02Z)
• Quasi-probabilities of work and heat in an open quantum system [0.0]
  We discuss an approach to determine averages of the work, dissipated heat and variation of internal energy of an open quantum system driven by an external classical field. We obtain a quasi-characteristic function and a quasi-probability density function for the corresponding observables. We use this feature to show that in the limit of strong dissipation, the quantum features vanish and interpret this as the emergence of the classical limit of the energy exchange process.
  arXiv  Detail & Related papers  (2021-10-12T06:55:39Z)
• Quantum-tailored machine-learning characterization of a superconducting qubit [50.591267188664666]
  We develop an approach to characterize the dynamics of a quantum device and learn device parameters. This approach outperforms physics-agnostic recurrent neural networks trained on numerically generated and experimental data. This demonstration shows how leveraging domain knowledge improves the accuracy and efficiency of this characterization task.
  arXiv  Detail & Related papers  (2021-06-24T15:58:57Z)
• Tomography in Loop Quantum Cosmology [0.0]
  We analyze the tomographic representation for the Friedmann-Robertson-Walker (FRW) model within the Loop Quantum Cosmology framework. We focus on the Wigner quasi-probability distributions associated with Gaussian and Schr"odinger cat states.
  arXiv  Detail & Related papers  (2021-04-20T02:31:52Z)
• Information Scrambling in Computationally Complex Quantum Circuits [56.22772134614514]
  We experimentally investigate the dynamics of quantum scrambling on a 53-qubit quantum processor. We show that while operator spreading is captured by an efficient classical model, operator entanglement requires exponentially scaled computational resources to simulate.
  arXiv  Detail & Related papers  (2021-01-21T22:18:49Z)
• Quantum Zeno effect appears in stages [64.41511459132334]
  In the quantum Zeno effect, quantum measurements can block the coherent oscillation of a two level system by freezing its state to one of the measurement eigenstates. We show that the onset of the Zeno regime is marked by a $textitcascade of transitions$ in the system dynamics as the measurement strength is increased.
  arXiv  Detail & Related papers  (2020-03-23T18:17:36Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.