Gate Optimization via Efficient Two-Qubit Benchmarking for NV Centers in Diamond

• URL: http://arxiv.org/abs/2603.08581v1
• Date: Mon, 09 Mar 2026 16:35:54 GMT
• Title: Gate Optimization via Efficient Two-Qubit Benchmarking for NV Centers in Diamond
• Abstract summary: We present an efficient method to evaluate the performance of a two-qubit gate by preparation and measurement of only two quantum states.<n>We tailor the approach to nitrogen-vacancy centers in diamond and, through numerical simulations, demonstrate how the method can optimize a two-qubit gate.
• Score: 35.18016233072556
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: High-fidelity gate implementation requires sophisticated control pulses that steer the quantum system to undergo the desired transformation. Quantum Optimal Control allows to derive these control pulses in an open-loop fashion based on numerical simulations. However, their precision can be limited by incomplete knowledge of the system. Closed-loop optimization overcomes this limitation by incorporating feedback from measurements, provided a suitable and efficient measure of the gate performance can be defined. In this article, we present an efficient method to evaluate the performance of a two-qubit gate by preparation and measurement of only two quantum states, enabling experimental closed-loop optimization with a metric previously believed to be limited to open-loop control. We tailor the approach to nitrogen-vacancy centers in diamond and, through numerical simulations, demonstrate how the method can optimize a two-qubit gate while reducing the number of required measurements by two orders of magnitude compared to standard process tomography under realistic experimental settings.

Related papers

• Pushing the Limits of Low-Bit Optimizers: A Focus on EMA Dynamics [64.62231094774211]
  Statefuls (e.g., Adam) maintain auxiliary information even 2x the model size in order to achieve optimal convergence.<n>SOLO enables Adam-styles to maintain quantized states with precision as low as 3 bits, or even 2 bits.<n>SOLO can thus be seamlessly applied to Adam-styles, leading to substantial memory savings with minimal accuracy loss.
  arXiv  Detail & Related papers  (2025-05-01T06:47:45Z)
• Iterative Linear Quadratic Regulator for Quantum Optimal Control [4.8058614612509025]
  We establish a connection between the iterative linear quadratic regulator and quantum optimal control by adapting it to gate optimization of quantum systems.<n>We achieve high-fidelity simulation results for X and cross-resonance gates on one- and two-qubit fixed-frequency transmons simulated with two and three levels.
  arXiv  Detail & Related papers  (2025-04-15T07:36:32Z)
• Gradient projection method for constrained quantum control [46.08419608239004]
  We adopt the Gradient Projection Method (GPM) to problems of quantum control.<n>The main advantage of the method is that it allows to exactly satisfy the bounds.<n>We apply the GPM to several examples including generation of one- and two-qubit gates and two-qubit Bell and Werner states.
  arXiv  Detail & Related papers  (2024-11-29T11:56:55Z)
• Optimal control in large open quantum systems: the case of transmon readout and reset [44.99833362998488]
  We present a framework that combines the adjoint-state method together with reverse-time backpropagation to solve prohibitively large open-system quantum control problems.<n>We apply this framework to optimize two inherently dissipative operations in superconducting qubits.<n>Our results show that while standard pulses for dispersive readout are nearly optimal, adding a transmon drive during the protocol can yield 2x improvements in fidelity and duration.
  arXiv  Detail & Related papers  (2024-03-21T18:12:51Z)
• Gate-set evaluation metrics for closed-loop optimal control on nitrogen-vacancy center ensembles in diamond [0.0]
  We show how to apply quantum optimal control in an application-oriented fashion. We use a macroscopic ensemble of nitrogen-vacancy centers in diamond as a test-bed. Our work demonstrates the relative trade-offs between those measures and how to significantly enhance the gate-set performance.
  arXiv  Detail & Related papers  (2024-03-01T15:42:56Z)
• Pulse-controlled qubit in semiconductor double quantum dots [57.916342809977785]
  We present a numerically-optimized multipulse framework for the quantum control of a single-electron charge qubit. A novel control scheme manipulates the qubit adiabatically, while also retaining high speed and ability to perform a general single-qubit rotation.
  arXiv  Detail & Related papers  (2023-03-08T19:00:02Z)
• Direct pulse-level compilation of arbitrary quantum logic gates on superconducting qutrits [36.30869856057226]
  We demonstrate any arbitrary qubit and qutrit gate can be realized with high-fidelity, which can significantly reduce the length of a gate sequence. We show that optimal control gates are robust to drift for at least three hours and that the same calibration parameters can be used for all implemented gates.
  arXiv  Detail & Related papers  (2023-03-07T22:15:43Z)
• Multipoint-BAX: A New Approach for Efficiently Tuning Particle Accelerator Emittance via Virtual Objectives [47.52324722637079]
  We propose a new information-theoretic algorithm, Multipoint-BAX, for black-box optimization on multipoint queries. We use Multipoint-BAX to minimize emittance at the Linac Coherent Light Source (LCLS) and the Facility for Advanced Accelerator Experimental Tests II (FACET-II)
  arXiv  Detail & Related papers  (2022-09-10T04:01:23Z)
• Robustness of a universal gate set implementation in transmon systems via Chopped Random Basis optimal control [50.591267188664666]
  We numerically study the implementation of a universal two-qubit gate set, composed of CNOT, Hadamard, phase and $pi/8$ gates, for transmon-based systems. The control signals to implement such gates are obtained using the Chopped Random Basis optimal control technique, with a target gate infidelity of $10-2$.
  arXiv  Detail & Related papers  (2022-07-27T10:55:15Z)
• On optimization of coherent and incoherent controls for two-level quantum systems [77.34726150561087]
  This article considers some control problems for closed and open two-level quantum systems. The closed system's dynamics is governed by the Schr"odinger equation with coherent control. The open system's dynamics is governed by the Gorini-Kossakowski-Sudarshan-Lindblad master equation.
  arXiv  Detail & Related papers  (2022-05-05T09:08:03Z)
• Experimental Bayesian calibration of trapped ion entangling operations [48.43720700248091]
  We develop and characterize an efficient calibration protocol to automatically estimate and adjust experimental parameters of the widely used Molmer-Sorensen entangling gate operation. We experimentally demonstrate a median gate infidelity of $1.3(1)cdot10-3$, requiring only $1200pm500$ experimental cycles, while completing the entire gate calibration procedure in less than one minute.
  arXiv  Detail & Related papers  (2021-12-02T16:59:00Z)
• Optimization of Controlled-Z Gate with Data-Driven Gradient Ascent Pulse Engineering in a Superconducting Qubit System [2.5682124532812125]
  The experimental optimization of a two-qubit controlled-Z (CZ) gate is realized following two different data-driven gradient ascent pulse engineering (GRAPE) protocols. With an imperfect initial pulse in a flattop waveform, our experimental implementation shows that the CZ gate is quickly improved and the gate fidelities subject to the optimized two pulses are around 99%.
  arXiv  Detail & Related papers  (2021-04-24T12:04:33Z)
• Control optimization for parametric hamiltonians by pulse reconstruction [21.723487348914958]
  We propose a method to reduce the computational time required to generate the control pulse for a Hamiltonian. We use simple schemes to accurately reconstruct the control pulses from a set of pulses obtained in advance for a discrete set of predetermined parameter values.
  arXiv  Detail & Related papers  (2021-02-24T14:47:09Z)
• Quantum optimal control using phase-modulated driving fields [11.75064344240877]
  We devise a novel variant of a gradient-free optimal-control method by introducing the idea of phase-modulated driving fields. We numerically evaluate its performance and demonstrate the advantages over standard Fourier-basis methods in controlling an ensemble of two-level systems.
  arXiv  Detail & Related papers  (2020-09-22T02:07:47Z)

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.