Tomographic measurement data of states that never existed

• URL: http://arxiv.org/abs/2501.09424v2
• Date: Fri, 24 Jan 2025 19:23:09 GMT
• Title: Tomographic measurement data of states that never existed
• Authors: Julian Göttsch, Stephan Grebien, Felix Pein, Malte Lautzas, Daniela Abdelkhalek, Lorena Rebón, Boris Hage, Jaromír Fiurašek, Roman Schnabel,
• Abstract summary: Microscopic Schr"odinger cat states are generated from quantum correlated fields using a probabilistic heralding photon subtraction event. We present a new approach to derive measurement data of quantum correlated states with average quantum-correlated photon numbers significantly larger than one.
• Score: 0.0
• License:
• Abstract: Microscopic Schr{\"o}dinger cat states are generated from quantum correlated fields using a probabilistic heralding photon subtraction event. Subsequent quantum state tomography provides complete information about the state with typical photon numbers of the order of one. Another approach strives for a larger number of quantum-correlated photons by conditioning the measurement analysis on events with exactly this number of photons. Here, we present a new approach to derive measurement data of quantum correlated states with average quantum-correlated photon numbers significantly larger than one. We produce an ensemble of a heralded, photon-subtracted squeezed vacuum state of light. We split the states at a balanced beam splitter and simultaneously measure a pair of orthogonal field quadratures at the outputs using tomographic `Q-function homodyne detection' (QHD). The final act is probabilistic two-copy data post-processing aiming for data from a new state with larger photon number. Evaluating the final tomographic data as that of a grown microscopic Schr{\"o}dinger cat state shows that the probabilistic post-processing increased the photon number of $|\alpha_0|^2 \approx 1.2$ to $|\alpha_2|^2 \approx 6.8$. Our concept for obtaining tomographic measurement data of mesoscopic non-classical states that never existed might be a turning point in measurement-based quantum technology.

Related papers

• Deterministic and reconfigurable graph state generation with a single solid-state quantum emitter [0.0]
  We demonstrate deterministic and reconfigurable graph state generation with optical solid-state integrated quantum emitters. We perform quantum state tomography of two successive photons, measuring Bell state fidelities up to 0.80$pm$0.04 and concurrences up to 0.69$pm$0.09. This simple optical scheme, compatible with commercially available quantum dot-based single photon sources, brings us a step closer to fault-tolerant quantum computing with spins and photons.
  arXiv  Detail & Related papers  (2024-10-30T23:59:54Z)
• Generation of heralded optical `Schroedinger cat' states by photon-addition [3.093409936654924]
  We report the first experimental realization of optical "Schr"odinger cats" by adding a photon to a squeezed vacuum state. We generate "Schr"odinger cats" at rates exceeding $8.5 times 104$ counts per second.
  arXiv  Detail & Related papers  (2023-06-22T16:21:42Z)
• Quantum State Tomography for Matrix Product Density Operators [28.799576051288888]
  Reconstruction of quantum states from experimental measurements is crucial for the verification and benchmarking of quantum devices. Many physical quantum states, such as states generated by noisy, intermediate-scale quantum computers, are usually structured. We establish theoretical guarantees for the stable recovery of MPOs using tools from compressive sensing and the theory of empirical processes.
  arXiv  Detail & Related papers  (2023-06-15T18:23:55Z)
• Integrated Quantum Optical Phase Sensor [48.7576911714538]
  We present a photonic integrated circuit fabricated in thin-film lithium niobate. We use the second-order nonlinearity to produce a squeezed state at the same frequency as the pump light and realize circuit control and sensing with electro-optics. We anticipate that on-chip photonic systems like this, which operate with low power and integrate all of the needed functionality on a single die, will open new opportunities for quantum optical sensing.
  arXiv  Detail & Related papers  (2022-12-19T18:46:33Z)
• Schr\"odinger cat states of a 16-microgram mechanical oscillator [54.35850218188371]
  The superposition principle is one of the most fundamental principles of quantum mechanics. Here we demonstrate the preparation of a mechanical resonator with an effective mass of 16.2 micrograms in Schr"odinger cat states of motion. We show control over the size and phase of the superposition and investigate the decoherence dynamics of these states.
  arXiv  Detail & Related papers  (2022-11-01T13:29:44Z)
• Experimental demonstration of optimal unambiguous two-out-of-four quantum state elimination [52.77024349608834]
  A core principle of quantum theory is that non-orthogonal quantum states cannot be perfectly distinguished with single-shot measurements. Here we implement a quantum state elimination measurement which unambiguously rules out two of four pure, non-orthogonal quantum states.
  arXiv  Detail & Related papers  (2022-06-30T18:00:01Z)
• Study of decoherence of a superposition of macroscopic quantum states by means the consideration of a multimode state of a Schrodinger cat [0.0]
  Quantum Schrodinger cat states are of great interest in quantum communications and quantum optics. The analysis of the Schrodinger cat states coherence is an important task for their complete practical application. The research results have significant application and can be used in the development of high-dimensional quantum information processing systems.
  arXiv  Detail & Related papers  (2022-01-09T19:29:25Z)
• Bose-Einstein condensate soliton qubit states for metrological applications [58.720142291102135]
  We propose novel quantum metrology applications with two soliton qubit states. Phase space analysis, in terms of population imbalance - phase difference variables, is also performed to demonstrate macroscopic quantum self-trapping regimes.
  arXiv  Detail & Related papers  (2020-11-26T09:05:06Z)
• Generation of Schr\"odinger cat states through photon-assisted Landau-Zener-St\"uckelberg interferometry [0.0]
  We propose a conceptually new method for creating Schr"odinger cat states, based on photon-assisted Landau-Zener-St"uckelberg interferometry. We show that by initializing the qubit in one of its basis states, performing three consecutive sweeps of the qubit energy splitting across the 1-photon resonance, the parity of the photon field can be purified to very high degree.
  arXiv  Detail & Related papers  (2020-08-27T14:37:57Z)
• Weakly invasive metrology: quantum advantage and physical implementations [0.0]
  We show that arbitrarily intense coherent states can obtain information at a rate that scales at most linearly with $N_rm abs$ and $T$. We discuss an implementation in cavity QED, where Fock states are both prepared and measured by coupling atomic ensembles to the cavities.
  arXiv  Detail & Related papers  (2020-06-22T10:14:36Z)
• Jumptime unraveling of Markovian open quantum systems [68.8204255655161]
  We introduce jumptime unraveling as a distinct description of open quantum systems. quantum jump trajectories emerge, physically, from continuous quantum measurements. We demonstrate that quantum trajectories can also be ensemble-averaged at specific jump counts.
  arXiv  Detail & Related papers  (2020-01-24T09:35:32Z)

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.