Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:2206.14283

Narrowband composite two-qubit phase gates

Boyan T. Torosov, Nikolay V. Vitanov

Published Jun 28, 2022• 0 citations
arXivHTMLPDF

Abstract

We propose a method to construct composite two-qubit gates with narrowband profiles with respect to the spin-spin coupling. The composite sequences are selective to the variations in the amplitude and duration of the spin-spin coupling, and can be used for highly-selective qubit addressing with greatly reduced cross talk, quantum logic spectroscopy, and quantum sensing.

DOI
10.48550/arxiv.2206.14283

Related papers

Narrowband composite two-qubit gates for crosstalk suppression

Boyan T. Torosov, Nikolay V. Vitanov

We propose a method to construct composite two-qubit gates with narrowband profiles with respect to the spin-spin coupling. The composite sequences are selective to the variations in the amplitude and duration of the spin-spin coupling, and can be used for highly selective qubit addressing with greatly reduced crosstalk, quantum logic spectroscopy, and quantum sensing.

Physical Review A•Mar 27, 2023•6 citations

Narrowband and passband composite rotational quantum gates

Hayk L. Gevorgyan

High-precision, robust quantum gates are essential components in quantum computation and information processing. In this study, we present an alternative perspective, exploring the potential applicability of quantum gates that exhibit heightened sensitivity to errors. We investigate such sensitive quantum gates, which, beyond their established use in nuclear magnetic resonance spectroscopy and polarization optics, may offer significant utility in the other areas where selectivity, filtering, sensing, localization, or addressing properties are of interest. Utilizing the composite pulses technique, we derive three fundamental quantum gates with narrowband and passband characteristics—the () gate, the gate, and gates enabling arbitrary rotations. To systematically design these composite pulse sequences, we introduce the SU(2), modified-SU(2), and regularization random search methodologies. These approaches demonstrate superior performance compared to established sequences in the literature, including NB1, SK1, and PB1.

arXiv:2412.00939•Physical Review A•May 9, 2025•3 citations

High-fidelity error-resilient composite phase gates

Boyan T. Torosov, Nikolay V. Vitanov

We present a method to construct high-fidelity quantum phase gates, which are insensitive to errors in various experimental parameters. The phase gates consist of a pair of two sequential broadband composite pulses, with a phase difference $\ensuremath{\pi}+\ensuremath{\alpha}/2$ between them, where $\ensuremath{\alpha}$ is the desired gate phase. By using composite pulses which compensate systematic errors in the pulse area, the frequency detuning, or both the area and the detuning, we thereby construct composite phase gates which compensate errors in the same parameters. Particularly interesting are phase gates which use the recently discovered universal composite pulses, which compensate systematic errors in any parameter of the driving field, which keep the evolution Hermitian (e.g., pulse amplitude and duration, pulse shape, frequency detuning, Stark shifts, residual frequency chirps, etc.).

arXiv:1409.6410•Physical Review A•Jul 30, 2014•35 citations

High-fidelity composite quantum gates for Raman qubits

Boyan T. Torosov, Nikolay V. Vitanov

We present a general systematic approach to design robust and high-fidelity quantum logic gates with Raman qubits using the technique of composite pulses.We use two mathematical tools-the Morris-Shore and Majorana decompositions-to reduce the three-state Raman system to an equivalent two-state system.They allow us to exploit the numerous composite pulses designed for two-state systems by extending them to Raman qubits.We construct the NOT, Hadamard, and rotation gates by means of the Morris-Shore transformation with the same uniform approach: sequences of pulses with the same phases for each gate but different ratios of Raman couplings.The phase gate is constructed by using the Majorana decomposition.All composite Raman gates feature very high fidelity, well beyond the quantum computation benchmark values, and significant robustness to experimental errors.All composite phases and pulse areas are given by analytical formulas, which makes the method scalable to any desired accuracy and robustness to errors.

arXiv:2004.12810•Physical Review Research•Nov 6, 2020•17 citations

Robust Ising gates for practical quantum computation

Jonathan A. Jones

I describe the use of techniques based on composite rotations to combat systematic errors in controlled phase gates, which form the basis of two-qubit quantum logic gates. Although developed and described within the context of nuclear magnetic resonanace quantum computing these sequences should be applicable to any implementation of quantum computation based on Ising couplings. In combination with existing single-qubit gates this provides a universal set of robust quantum logic gates.

arXiv:quant-ph/0209049•Physical Review A•Jan 28, 2003•87 citations

Overcoming Stark-Shift Constraints in Phase-Controlled Rydberg Two-Qubit Gates

Ignacio R. Sola, Sebastian C. Carrasco, Vladimir S. Malinovsky +2 more

Stark shifts introduce additional phases that constrain the set of entangling gates that can be prepared via two-photon transitions in the strong Rydberg blockade limit. For non-independently addressed qubits, by controlling the absolute phases and the local amplitudes of the pulses at each qubit, we show that any two-qubit phase gate can be prepared with high fidelity using a three-pulse sequence. Based on these insights, we introduce two robust control schemes tailored to different phase gates that yield better results with pulse sequences of either even or odd length.

quant-pharXiv:2601.01521•Physical Review A•Jan 6, 2026•0 citations
We propose a method to construct composite two-qubit gates with narrowband profiles with respect to the spin-spin coupling. The composite sequences are selective to the variations in the amplitude and duration of the spin-spin coupling, and can be used for highly-selective qubit addressing with greatly reduced cross talk, quantum logic spectroscopy, and quantum sensing.
High-precision, robust quantum gates are essential components in quantum computation and information processing. In this study, we present an alternative perspective, exploring the potential applicability of quantum gates that exhibit heightened sensitivity to errors. We investigate such sensitive quantum gates, which, beyond their established use in nuclear magnetic resonance spectroscopy and polarization optics, may offer significant utility in the other areas where selectivity, filtering, sensing, localization, or addressing properties are of interest. Utilizing the composite pulses technique, we derive three fundamental quantum gates with narrowband and passband characteristics—the () gate, the gate, and gates enabling arbitrary rotations. To systematically design these composite pulse sequences, we introduce the SU(2), modified-SU(2), and regularization random search methodologies. These approaches demonstrate superior performance compared to established sequences in the literature, including NB1, SK1, and PB1.
We present a method to construct high-fidelity quantum phase gates, which are insensitive to errors in various experimental parameters. The phase gates consist of a pair of two sequential broadband composite pulses, with a phase difference $\ensuremath{\pi}+\ensuremath{\alpha}/2$ between them, where $\ensuremath{\alpha}$ is the desired gate phase. By using composite pulses which compensate systematic errors in the pulse area, the frequency detuning, or both the area and the detuning, we thereby construct composite phase gates which compensate errors in the same parameters. Particularly interesting are phase gates which use the recently discovered universal composite pulses, which compensate systematic errors in any parameter of the driving field, which keep the evolution Hermitian (e.g., pulse amplitude and duration, pulse shape, frequency detuning, Stark shifts, residual frequency chirps, etc.).
We present a general systematic approach to design robust and high-fidelity quantum logic gates with Raman qubits using the technique of composite pulses.We use two mathematical tools-the Morris-Shore and Majorana decompositions-to reduce the three-state Raman system to an equivalent two-state system.They allow us to exploit the numerous composite pulses designed for two-state systems by extending them to Raman qubits.We construct the NOT, Hadamard, and rotation gates by means of the Morris-Shore transformation with the same uniform approach: sequences of pulses with the same phases for each gate but different ratios of Raman couplings.The phase gate is constructed by using the Majorana decomposition.All composite Raman gates feature very high fidelity, well beyond the quantum computation benchmark values, and significant robustness to experimental errors.All composite phases and pulse areas are given by analytical formulas, which makes the method scalable to any desired accuracy and robustness to errors.
Stark shifts introduce additional phases that constrain the set of entangling gates that can be prepared via two-photon transitions in the strong Rydberg blockade limit. For non-independently addressed qubits, by controlling the absolute phases and the local amplitudes of the pulses at each qubit, we show that any two-qubit phase gate can be prepared with high fidelity using a three-pulse sequence. Based on these insights, we introduce two robust control schemes tailored to different phase gates that yield better results with pulse sequences of either even or odd length.