High-fidelity QND readout and measurement back-action in a Tantalum-based high-coherence fluxonium qubit

• URL: http://arxiv.org/abs/2501.16691v1
• Date: Tue, 28 Jan 2025 03:59:29 GMT
• Title: High-fidelity QND readout and measurement back-action in a Tantalum-based high-coherence fluxonium qubit
• Authors: Gaurav Bothara, Srijita Das, Kishor V Salunkhe, Madhavi Chand, Jay Deshmukh, Meghan P Patankar, R Vijay,
• Abstract summary: We study the measurement characteristics of a tantalum-based high-coherence fluxonium qubit. We find that the measurement fidelity and QND nature are limited by state-mixing errors.
• Score: 1.1443262816483672
• License:
• Abstract: Implementing a precise measurement of the quantum state of a qubit is very critical for building a practical quantum processor as it plays an important role in state initialization and quantum error correction. While the transmon qubit has been the most commonly used design in small to medium-scale processors, the fluxonium qubit is emerging as a strong alternative with the potential for high-fidelity gate operation as a result of the high anharmonicity and high coherence achievable due to its unique design. Here, we explore the measurement characteristics of a tantalum-based high-coherence fluxonium qubit and demonstrate single-shot measurement fidelity (assignment fidelity) of 96.2% and 97.8% without and with the use of a Josephson Parametric Amplifier respectively. We study the back-action of the measurement photons on the qubit and measure a QND (repeatability) fidelity of 99.6%. We find that the measurement fidelity and QND nature are limited by state-mixing errors and our results suggest that a careful study of measurement-induced transitions in the fluxonium is needed to further optimize the readout performance.

Related papers

• 99.9%-fidelity in measuring a superconducting qubit [7.469716894645766]
  Quantum state measurement lags nearly an order of magnitude behind quantum gate operations in speed and fidelity. Here, we design a novel architecture to implement the long-sought longitudinal interaction scheme between qubits and resonators. Our experimental results demonstrate a measurement fidelity of 99.8% in 202 ns without the need for any first-stage amplification.
  arXiv  Detail & Related papers  (2024-12-18T13:45:13Z)
• Improved fluxonium readout through dynamic flux pulsing [4.273820097694244]
  In this work, we experimentally demonstrate flux-pulse-assisted readout of a fluxonium qubit. We achieve an assignment fidelity of 94.3% with an integration time of 280 ns. Results constitute the fastest reported readout of a fluxonium qubit.
  arXiv  Detail & Related papers  (2024-11-20T16:25:44Z)
• Generalized Parity Measurements and Efficient Large Multi-component Cat State Preparation with Quantum Signal Processing [0.0]
  Generalized parity measurements are instrumental for the preparation of non-trivial quantum states. We show a proposal for efficient and robust generalized parity measurements based on Quantum Signal Processing.
  arXiv  Detail & Related papers  (2024-09-08T18:47:22Z)
• Design and simulation of a transmon qubit chip for Axion detection [103.69390312201169]
  Device based on superconducting qubits has been successfully applied in detecting few-GHz single photons via Quantum Non-Demolition measurement (QND) In this study, we present Qub-IT's status towards the realization of its first superconducting qubit device.
  arXiv  Detail & Related papers  (2023-10-08T17:11:42Z)
• Model-based Optimization of Superconducting Qubit Readout [59.992881941624965]
  We demonstrate model-based readout optimization for superconducting qubits. We observe 1.5% error per qubit with a 500ns end-to-end duration and minimal excess reset error from residual resonator photons. This technique can scale to hundreds of qubits and be used to enhance the performance of error-correcting codes and near-term applications.
  arXiv  Detail & Related papers  (2023-08-03T23:30:56Z)
• Adaptive Quantum Tomography in a Weak Measurement System with Superconducting Circuits [0.0]
  We introduce a new optimal measurement basis to achieve fast adaptive quantum state tomography. We expect that the adaptive quantum state tomography protocol can lead to a reduction in the number of required measurements of approximately 33.74%. Experimentally, we find a 14.81% measurement number reduction in a superconducting circuit system.
  arXiv  Detail & Related papers  (2023-05-08T09:43:03Z)
• Anticipative measurements in hybrid quantum-classical computation [68.8204255655161]
  We present an approach where the quantum computation is supplemented by a classical result. Taking advantage of its anticipation also leads to a new type of quantum measurements, which we call anticipative. In an anticipative quantum measurement the combination of the results from classical and quantum computations happens only in the end.
  arXiv  Detail & Related papers  (2022-09-12T15:47:44Z)
• First design of a superconducting qubit for the QUB-IT experiment [50.591267188664666]
  The goal of the QUB-IT project is to realize an itinerant single-photon counter exploiting Quantum Non Demolition (QND) measurements and entangled qubits. We present the design and simulation of the first superconducting device consisting of a transmon qubit coupled to a resonator using Qiskit-Metal.
  arXiv  Detail & Related papers  (2022-07-18T07:05:10Z)
• Analytical and experimental study of center line miscalibrations in M\o lmer-S\o rensen gates [51.93099889384597]
  We study a systematic perturbative expansion in miscalibrated parameters of the Molmer-Sorensen entangling gate. We compute the gate evolution operator which allows us to obtain relevant key properties. We verify the predictions from our model by benchmarking them against measurements in a trapped-ion quantum processor.
  arXiv  Detail & Related papers  (2021-12-10T10:56:16Z)
• 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)
• Efficient qubit measurement with a nonreciprocal microwave amplifier [0.0]
  We demonstrate the efficient measurement of a superconducting qubit using a nonreciprocal parametric amplifier. In addition to providing tools for further improving the fidelity of strong projective measurement, this work creates a testbed for the experimental study of ideal weak measurements.
  arXiv  Detail & Related papers  (2020-09-18T14:40:38Z)

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.