Quantum Process Tomography with Digital Twins of Error Matrices

• URL: http://arxiv.org/abs/2505.07725v1
• Date: Mon, 12 May 2025 16:34:41 GMT
• Title: Quantum Process Tomography with Digital Twins of Error Matrices
• Authors: Tangyou Huang, Akshay Gaikwad, Ilya Moskalenko, Anuj Aggarwal, Tahereh Abad, Marko Kuzmanovic, Yu-Han Chang, Ognjen Stanisavljevic, Emil Hogedal, Christopher Warren, Irshad Ahmad, Janka Biznárová, Amr Osman, Mamta Dahiya, Marcus Rommel, Anita Fadavi Rousari, Andreas Nylander, Liangyu Chen, Jonas Bylander, Gheorghe Sorin Paraoanu, Anton Frisk Kockum, Giovanna Tancredi,
• Abstract summary: We propose and investigate enhanced quantum process tomography (QPT) for multi-qubit systems.<n>We integrate the error matrix in a digital twin of the identity process matrix, enabling statistical refinement of SPAM error learning.<n>Our results provide a practical and precise method for assessing quantum gate fidelity and enhancing QPT on a given hardware.
• Score: 2.613906407314356
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: Accurate and robust quantum process tomography (QPT) is crucial for verifying quantum gates and diagnosing implementation faults in experiments aimed at building universal quantum computers. However, the reliability of QPT protocols is often compromised by faulty probes, particularly state preparation and measurement (SPAM) errors, which introduce fundamental inconsistencies in traditional QPT algorithms. We propose and investigate enhanced QPT for multi-qubit systems by integrating the error matrix in a digital twin of the identity process matrix, enabling statistical refinement of SPAM error learning and improving QPT precision. Through numerical simulations, we demonstrate that our approach enables highly accurate and faithful process characterization. We further validate our method experimentally using superconducting quantum gates, achieving at least an order-of-magnitude fidelity improvement over standard QPT. Our results provide a practical and precise method for assessing quantum gate fidelity and enhancing QPT on a given hardware.

Related papers

• Advancing quantum process tomography through universal compilation [0.0]
  Quantum process tomography (QPT) is crucial for characterizing operations in quantum gates and circuits.<n>Here, we propose a QPT approach based on universal compilation, which systematically decomposes quantum processes into optimized Kraus operators and Choi matrices.<n>We benchmark our approach through numerical simulations of random unitary gates, demonstrating highly accurate quantum process characterization.
  arXiv  Detail & Related papers  (2025-04-21T08:34:33Z)
• Benchmarking quantum gates and circuits [1.6163129903911515]
  This paper reviews a variety of key benchmarking techniques, including Randomized Benchmarking, Quantum Process Tomography, Gate Set Tomography, Process Fidelity Estimation, Direct Fidelity Estimation, and Cross-Entropy Benchmarking.<n>We introduce deterministic benchmarking (DB), a novel protocol that minimizes the number of experimental runs, exhibits resilience to SPAM errors, and effectively characterizes both coherent and incoherent errors.
  arXiv  Detail & Related papers  (2024-07-13T16:36:02Z)
• Multipass Quantum Process Tomography: Precision and Accuracy Enhancement [0.0]
  We introduce a method to enhance the precision and accuracy of Quantum Process Tomography (QPT) Instead of performing QPT solely on a single gate, we propose performing QPT on a sequence of multiple applications of the same gate. We use the proposed method to experimentally determine the PTM and the fidelity of the CNOT gate on the quantum processor ibmq_manila (Falcon r5.11L)
  arXiv  Detail & Related papers  (2024-02-06T16:26:18Z)
• Mitigating Errors on Superconducting Quantum Processors through Fuzzy Clustering [38.02852247910155]
  A new Quantum Error Mitigation (QEM) technique uses Fuzzy C-Means clustering to specifically identify measurement error patterns. We report a proof-of-principle validation of the technique on a 2-qubit register, obtained as a subset of a real NISQ 5-qubit superconducting quantum processor. We demonstrate that the FCM-based QEM technique allows for reasonable improvement of the expectation values of single- and two-qubit gates based quantum circuits.
  arXiv  Detail & Related papers  (2024-02-02T14:02:45Z)
• Compilation of a simple chemistry application to quantum error correction primitives [44.99833362998488]
  We estimate the resources required to fault-tolerantly perform quantum phase estimation on a minimal chemical example. We find that implementing even a simple chemistry circuit requires 1,000 qubits and 2,300 quantum error correction rounds.
  arXiv  Detail & Related papers  (2023-07-06T18:00:10Z)
• Virtual quantum error detection [0.17999333451993949]
  We propose a protocol called virtual quantum error detection (VQED) VQED virtually allows for evaluating computation results corresponding to post-selected quantum states obtained through quantum error detection. For some simple error models, the results obtained using VQED are robust against the noise that occurred during the operation of VQED.
  arXiv  Detail & Related papers  (2023-02-06T08:52:50Z)
• Potential and limitations of quantum extreme learning machines [55.41644538483948]
  We present a framework to model QRCs and QELMs, showing that they can be concisely described via single effective measurements. Our analysis paves the way to a more thorough understanding of the capabilities and limitations of both QELMs and QRCs.
  arXiv  Detail & Related papers  (2022-10-03T09:32:28Z)
• Quantum circuit debugging and sensitivity analysis via local inversions [62.997667081978825]
  We present a technique that pinpoints the sections of a quantum circuit that affect the circuit output the most. We demonstrate the practicality and efficacy of the proposed technique by applying it to example algorithmic circuits implemented on IBM quantum machines.
  arXiv  Detail & Related papers  (2022-04-12T19:39:31Z)
• 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)
• Circuit Symmetry Verification Mitigates Quantum-Domain Impairments [69.33243249411113]
  We propose circuit-oriented symmetry verification that are capable of verifying the commutativity of quantum circuits without the knowledge of the quantum state. In particular, we propose the Fourier-temporal stabilizer (STS) technique, which generalizes the conventional quantum-domain formalism to circuit-oriented stabilizers.
  arXiv  Detail & Related papers  (2021-12-27T21:15:35Z)
• Sampling Overhead Analysis of Quantum Error Mitigation: Uncoded vs. Coded Systems [69.33243249411113]
  We show that Pauli errors incur the lowest sampling overhead among a large class of realistic quantum channels. We conceive a scheme amalgamating QEM with quantum channel coding, and analyse its sampling overhead reduction compared to pure QEM.
  arXiv  Detail & Related papers  (2020-12-15T15:51:27Z)
• Using Quantum Metrological Bounds in Quantum Error Correction: A Simple Proof of the Approximate Eastin-Knill Theorem [77.34726150561087]
  We present a proof of the approximate Eastin-Knill theorem, which connects the quality of a quantum error-correcting code with its ability to achieve a universal set of logical gates. Our derivation employs powerful bounds on the quantum Fisher information in generic quantum metrological protocols.
  arXiv  Detail & Related papers  (2020-04-24T17:58:10Z)

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.