Over-rotation coherent error in quantum gates subjected to pseudo twirling

• URL: http://arxiv.org/abs/2407.06055v1
• Date: Mon, 8 Jul 2024 15:56:09 GMT
• Title: Over-rotation coherent error in quantum gates subjected to pseudo twirling
• Authors: Tanmoy Pandit, Raam Uzdin,
• Abstract summary: Coherence errors are a significant challenge to the scalability of quantum computing. We show that a framework called pseudo-twirling (PST) for treating coherent error in multi-qubit non-Clifford gates has been introduced and experimentally demonstrated. Although the small induced over-rotation can amount to a significant coherent error in deep circuits, we explain why it does not degrade the performance of the gate.
• Score: 0.0
• License: http://creativecommons.org/licenses/by-nc-sa/4.0/
• Abstract: Quantum error mitigation schemes (QEM) have greatly enhanced the efficiency of quantum computers, specifically focusing on reducing errors caused by interactions with the environment. Nevertheless, the presence of coherence errors, typically arising from miscalibration and inter-qubit crosstalk, is a significant challenge to the scalability of quantum computing. Such errors are often addressed using a refined Pauli twirling scheme called Randomized Compiling (RC) that converts the coherent errors into incoherent errors that can then be mitigated by conventional QEM. Unfortunately for multi-qubit gates, RC is restricted to Clifford gates such as CNOT and CPHASE. However, it has been demonstrated experimentally that a direct implementation of multi-qubit non-Clifford gates, i.e. without using multi-qubit Clifford gates, has reduced the depth of the circuit by a factor of four and more. Recently, a framework called pseudo-twirling (PST) for treating coherent error in multi-qubit non-Clifford gates has been introduced and experimentally demonstrated. We show analytically that a higher order correction to the existing PST theory yields an over-rotation coherent error generated by the PST protocol itself. This PST effect has no analogue in RC. Although the small induced over-rotation can amount to a significant coherent error in deep circuits, we explain why it does not degrade the performance of the gate.

Related papers

• Pseudo Twirling Mitigation of Coherent Errors in non-Clifford Gates [0.0]
  We introduce, analyzes, and experimentally demonstrate a technique called Pseudo Twirling' to address coherent errors in general gates and circuits. We experimentally showcase that integrating pseudo twirling with a quantum error mitigation method called Adaptive KIK' enables the simultaneous mitigation of both noise and coherent errors in non-Clifford gates.
  arXiv  Detail & Related papers  (2024-01-17T08:14:59Z)
• Averaging gate approximation error and performance of Unitary Coupled Cluster ansatz in Pre-FTQC Era [0.0]
  Fault-tolerant quantum computation (FTQC) is essential to implement quantum algorithms in a noise-resilient way. In FTQC, a quantum circuit is decomposed into universal gates that can be fault-tolerantly implemented. In this paper, we propose that the Clifford+$T$ decomposition error for a given quantum circuit can be modeled as the depolarizing noise.
  arXiv  Detail & Related papers  (2023-01-10T19:00:01Z)
• Witnessing entanglement in trapped-ion quantum error correction under realistic noise [41.94295877935867]
  Quantum Error Correction (QEC) exploits redundancy by encoding logical information into multiple physical qubits. We present a detailed microscopic error model to estimate the average gate infidelity of two-qubit light-shift gates used in trapped-ion platforms. We then apply this realistic error model to quantify the multipartite entanglement generated by circuits that act as QEC building blocks.
  arXiv  Detail & Related papers  (2022-12-14T20:00:36Z)
• Single-shot error mitigation by coherent Pauli checks [6.992823294269743]
  We show how to generate samples from the output distribution of a quantum circuit without full-blown error correction. Our approach is based on Coherent Pauli Checks that detect errors in a Clifford circuit.
  arXiv  Detail & Related papers  (2022-12-07T20:03:07Z)
• 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)
• Software mitigation of coherent two-qubit gate errors [55.878249096379804]
  Two-qubit gates are important components of quantum computing. But unwanted interactions between qubits (so-called parasitic gates) can degrade the performance of quantum applications. We present two software methods to mitigate parasitic two-qubit gate errors.
  arXiv  Detail & Related papers  (2021-11-08T17:37:27Z)
• Fault-tolerant parity readout on a shuttling-based trapped-ion quantum computer [64.47265213752996]
  We experimentally demonstrate a fault-tolerant weight-4 parity check measurement scheme. We achieve a flag-conditioned parity measurement single-shot fidelity of 93.2(2)%. The scheme is an essential building block in a broad class of stabilizer quantum error correction protocols.
  arXiv  Detail & Related papers  (2021-07-13T20:08:04Z)
• Crosstalk Suppression for Fault-tolerant Quantum Error Correction with Trapped Ions [62.997667081978825]
  We present a study of crosstalk errors in a quantum-computing architecture based on a single string of ions confined by a radio-frequency trap, and manipulated by individually-addressed laser beams. This type of errors affects spectator qubits that, ideally, should remain unaltered during the application of single- and two-qubit quantum gates addressed at a different set of active qubits. We microscopically model crosstalk errors from first principles and present a detailed study showing the importance of using a coherent vs incoherent error modelling and, moreover, discuss strategies to actively suppress this crosstalk at the gate level.
  arXiv  Detail & Related papers  (2020-12-21T14:20:40Z)
• 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.