Quantum tomography for quantum systems optimization

• URL: http://arxiv.org/abs/2201.03255v1
• Date: Mon, 10 Jan 2022 10:18:35 GMT
• Title: Quantum tomography for quantum systems optimization
• Authors: B. I. Bantysh, Yu. I. Bogdanov
• Abstract summary: We investigate the possibility of estimating errors from experiment. These estimates are subsequently used to build a robust quantum tomography model. We show that, having such imperfect single-qubit gates with pre-estimated errors, one can obtain transformations close to ideal ones.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Debugging quantum states transformations is an important task of modern quantum computing. The use of quantum tomography for these purposes significantly expands the range of possibilities. However, the presence of preparation and measurement errors complicates the practical use of this procedure. In this work, we investigate the possibility of estimating these errors from experiment. These estimates are subsequently used to build a robust quantum tomography model. The model allows one to accurately reconstruct unitary errors of single-qubit gates. We show that, having such imperfect single-qubit gates with pre-estimated errors, one can obtain transformations close to ideal ones. A similar approach can also significantly mitigate single-qubit gates cross-talk.

Related papers

• Hamiltonian Phase Error in Resonantly Driven CNOT Gate Above the Fault-Tolerant Threshold [0.0]
  electron spin qubits are a promising platform for scalable quantum processors. A full-fledged quantum computer will need quantum error correction, which requires high-fidelity quantum gates. We demonstrate a simple yet reliable calibration procedure for a high-fidelity controlled-rotation gate in an exchange-always-on Silicon quantum processor.
  arXiv  Detail & Related papers  (2023-07-18T07:44:00Z)
• Quantum process tomography of continuous-variable gates using coherent states [49.299443295581064]
  We demonstrate the use of coherent-state quantum process tomography (csQPT) for a bosonic-mode superconducting circuit. We show results for this method by characterizing a logical quantum gate constructed using displacement and SNAP operations on an encoded qubit.
  arXiv  Detail & Related papers  (2023-03-02T18:08:08Z)
• Syndrome-Derived Error Rates as a Benchmark of Quantum Hardware [0.0]
  Quantum error correcting codes are designed to pinpoint exactly when and where errors occur in quantum circuits. By analyzing the outputs of even small-scale quantum error correction circuits, a detailed picture can be constructed of error processes across a quantum device.
  arXiv  Detail & Related papers  (2022-07-01T17:10:51Z)
• Measuring NISQ Gate-Based Qubit Stability Using a 1+1 Field Theory and Cycle Benchmarking [50.8020641352841]
  We study coherent errors on a quantum hardware platform using a transverse field Ising model Hamiltonian as a sample user application. We identify inter-day and intra-day qubit calibration drift and the impacts of quantum circuit placement on groups of qubits in different physical locations on the processor. This paper also discusses how these measurements can provide a better understanding of these types of errors and how they may improve efforts to validate the accuracy of quantum computations.
  arXiv  Detail & Related papers  (2022-01-08T23:12:55Z)
• 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)
• Mitigating Quantum Errors via Truncated Neumann Series [10.04862322536857]
  We propose a unified framework that can mitigate quantum gate and measurement errors in computing quantum expectation values. The essential idea is to cancel the effect of quantum error by approximating its inverse via linearly combining quantum errors of different orders. We test this framework for different quantum errors and find that the computation accuracy is substantially improved.
  arXiv  Detail & Related papers  (2021-11-01T04:16:49Z)
• Characterizing quantum instruments: from non-demolition measurements to quantum error correction [48.43720700248091]
  In quantum information processing quantum operations are often processed alongside measurements which result in classical data. Non-unitary dynamical processes can take place on the system, for which common quantum channel descriptions fail to describe the time evolution. Quantum measurements are correctly treated by means of so-called quantum instruments capturing both classical outputs and post-measurement quantum states.
  arXiv  Detail & Related papers  (2021-10-13T18:00:13Z)
• Hardware-Efficient, Fault-Tolerant Quantum Computation with Rydberg Atoms [55.41644538483948]
  We provide the first complete characterization of sources of error in a neutral-atom quantum computer. We develop a novel and distinctly efficient method to address the most important errors associated with the decay of atomic qubits to states outside of the computational subspace. Our protocols can be implemented in the near-term using state-of-the-art neutral atom platforms with qubits encoded in both alkali and alkaline-earth atoms.
  arXiv  Detail & Related papers  (2021-05-27T23:29:53Z)
• Quantum tomography of noisy ion-based qudits [0.0]
  We show that it is possible to construct a quantum measurement protocol that contains no more than a single quantum operation in each measurement circuit. The measures described can significantly improve the accuracy of quantum tomography of real ion-based qudits.
  arXiv  Detail & Related papers  (2020-11-09T04:10:32Z)
• Semi-device-dependent blind quantum tomography [1.3075880857448061]
  Current schemes typically require measurement devices for tomography that are a priori calibrated to high precision. We show that exploiting the natural low-rank structure of quantum states of interest suffices to arrive at a highly scalable blind' tomography scheme. We numerically demonstrate that robust blind quantum tomography is possible in a practical setting inspired by an implementation of trapped ions.
  arXiv  Detail & Related papers  (2020-06-04T18:00:04Z)
• Deterministic correction of qubit loss [48.43720700248091]
  Loss of qubits poses one of the fundamental obstacles towards large-scale and fault-tolerant quantum information processors. We experimentally demonstrate the implementation of a full cycle of qubit loss detection and correction on a minimal instance of a topological surface code.
  arXiv  Detail & Related papers  (2020-02-21T19:48:53Z)

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.