Squeezing of nonlinear spin observables by one axis twisting in the presence of decoherence: An analytical study

• URL: http://arxiv.org/abs/2112.01786v1
• Date: Fri, 3 Dec 2021 08:38:40 GMT
• Title: Squeezing of nonlinear spin observables by one axis twisting in the presence of decoherence: An analytical study
• Authors: Youcef Baamara (LKB (Lhomond)), Alice Sinatra (LKB (Lhomond)), Manuel Gessner (LKB (Lhomond), ICFO)
• Abstract summary: Non-Gaussian spin states can produce larger quantum enhancements than spin-squeezed Gaussian states. We show that measurement-after-interaction techniques are effective in measuring nonlinear spin observables.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: In an ensemble of two-level atoms that can be described in terms of a collective spin, entangled states can be used to enhance the sensitivity of interferometric precision measurements. While non-Gaussian spin states can produce larger quantum enhancements than spin-squeezed Gaussian states, their use requires the measurement of observables that are nonlinear functions of the three components of the collective spin. In this paper we develop strategies that achieve the optimal quantum enhancements using non-Gaussian states produced by a nonlinear one-axis-twisting Hamiltonian, and show that measurement-after-interaction techniques, known to amplify the output signals in quantum parameter estimation protocols, are effective in measuring nonlinear spin observables. Including the presence of the relevant decoherence processes from atomic experiments, we determine analytically the quantum enhancement of non-Gaussian over-squeezed states as a function of the noise parameters for arbitrary atom numbers.

Related papers

• Fourier Neural Operators for Learning Dynamics in Quantum Spin Systems [77.88054335119074]
  We use FNOs to model the evolution of random quantum spin systems. We apply FNOs to a compact set of Hamiltonian observables instead of the entire $2n$ quantum wavefunction.
  arXiv  Detail & Related papers  (2024-09-05T07:18:09Z)
• Quantum metrology with a squeezed Kerr oscillator [0.0]
  We study the squeezing dynamics in a Kerr-nonlinear oscillator, and quantify the metrological usefulness of the resulting states. We propose the use of a measurement-after-interaction protocol where a linear quadrature measurement is preceded by an additional nonlinear evolution. Our results are robust when considering realistic imperfections such as energy relaxation, and can be implemented in state-of-the-art experimental setups.
  arXiv  Detail & Related papers  (2024-06-17T17:41:03Z)
• Optimal quantum sensing of the nonlinear bosonic interactions using Fock states [0.0]
  processes with individual quanta beyond bilinear interactions are essential for quantum technology with bosonic systems. We derive non-trivial, but optimal strategies for sensing the basic and experimentally available trilinear interactions using non-trivial particle-like Fock states. It can reveal unexplored aspects of nonlinear dynamics relevant to using such nonlinear processes in bosonic experiments with trapped ions and superconducting circuits.
  arXiv  Detail & Related papers  (2024-04-27T13:53:11Z)
• Observation of partial and infinite-temperature thermalization induced by repeated measurements on a quantum hardware [62.997667081978825]
  We observe partial and infinite-temperature thermalization on a quantum superconducting processor. We show that the convergence does not tend to a completely mixed (infinite-temperature) state, but to a block-diagonal state in the observable basis.
  arXiv  Detail & Related papers  (2022-11-14T15:18:11Z)
• Characterizing Multipartite Non-Gaussian Entanglement for Three-Mode Spontaneous Parametric Down-Conversion Process [13.641728072655278]
  We present an experimentally practical method to characterize continuous-variable multipartite non-Gaussian entanglement. We show that our method can be readily used to confirm fully inseparable tripartite non-Gaussian entangled states.
  arXiv  Detail & Related papers  (2022-07-14T03:22:22Z)
• Quantum probes for the characterization of nonlinear media [50.591267188664666]
  We investigate how squeezed probes may improve individual and joint estimation of the nonlinear coupling $tildelambda$ and of the nonlinearity order $zeta$. We conclude that quantum probes represent a resource to enhance precision in the characterization of nonlinear media, and foresee potential applications with current technology.
  arXiv  Detail & Related papers  (2021-09-16T15:40:36Z)
• Enhanced nonlinear quantum metrology with weakly coupled solitons and particle losses [58.720142291102135]
  We offer an interferometric procedure for phase parameters estimation at the Heisenberg (up to 1/N) and super-Heisenberg scaling levels. The heart of our setup is the novel soliton Josephson Junction (SJJ) system providing the formation of the quantum probe. We illustrate that such states are close to the optimal ones even with moderate losses.
  arXiv  Detail & Related papers  (2021-08-07T09:29:23Z)
• Designing Kerr Interactions for Quantum Information Processing via Counterrotating Terms of Asymmetric Josephson-Junction Loops [68.8204255655161]
  static cavity nonlinearities typically limit the performance of bosonic quantum error-correcting codes. Treating the nonlinearity as a perturbation, we derive effective Hamiltonians using the Schrieffer-Wolff transformation. Results show that a cubic interaction allows to increase the effective rates of both linear and nonlinear operations.
  arXiv  Detail & Related papers  (2021-07-14T15:11:05Z)
• Cubic nonlinear squeezing and its decoherence [1.2891210250935146]
  We analyze the behavior of quantum states with cubic nonlinear squeezing under loss and dephasing. The properties of nonlinear squeezed states depend on their initial parameters which can be optimized and adjusted to achieve the maximal robustness for the potential applications.
  arXiv  Detail & Related papers  (2021-07-13T12:43:19Z)
• Visualizing spinon Fermi surfaces with time-dependent spectroscopy [62.997667081978825]
  We propose applying time-dependent photo-emission spectroscopy, an established tool in solid state systems, in cold atom quantum simulators. We show in exact diagonalization simulations of the one-dimensional $t-J$ model that the spinons start to populate previously unoccupied states in an effective band structure. The dependence of the spectral function on the time after the pump pulse reveals collective interactions among spinons.
  arXiv  Detail & Related papers  (2021-05-27T18:00:02Z)
• Metrological characterisation of non-Gaussian entangled states of superconducting qubits [17.079776889091058]
  Non-Gaussian entangled states are predicted to achieve a higher sensitivity of precision measurements than Gaussian states. Using a 19-qubit programmable superconducting processor, here we report the characterisation of multiparticle entangled states generated during its nonlinear dynamics.
  arXiv  Detail & Related papers  (2021-03-21T16:39:25Z)

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.