4.5 Article

Designing Filter Functions of Frequency-Modulated Pulses for High-Fidelity Two-Qubit Gates in Ion Chains

Related references

Note: Only part of the references are listed.
Article Multidisciplinary Sciences

Demonstration of fault-tolerant universal quantum gate operations

Lukas Postler et al.

Summary: In this study, a fault-tolerant universal gate set for two logical qubits in a trapped-ion quantum computer is demonstrated. The presence or absence of errors is indicated by auxiliary flag qubits using the paradigm of flag fault tolerance. The hallmark feature of fault tolerance is observed, paving the way for error-corrected universal quantum computation.

NATURE (2022)

Article Physics, Applied

Hidden Inverses: Coherent Error Cancellation at the Circuit Level

Bichen Zhang et al.

Summary: In this paper, a method for reducing coherent errors by using hidden inverses is demonstrated. The effectiveness of this method is numerically simulated and experimentally validated on a trapped-ion quantum computer.

PHYSICAL REVIEW APPLIED (2022)

Article Physics, Multidisciplinary

Crosstalk Suppression in Individually Addressed Two-Qubit Gates in a Trapped-Ion Quantum Computer

Chao Fang et al.

Summary: In quantum computers, crosstalk between the target and neighboring spectator qubits due to the spillover of control signals is a major error source limiting the fidelity of two-qubit entangling gates. This study proposes a crosstalk suppression scheme that eliminates all first-order crosstalk using only local control of the target qubits, as opposed to existing schemes. Experimental results in a laser-driven trapped-ion system show high fidelity for the two-qubit Bell state, indicating the potential applicability of this scheme to other platforms with analogous interaction Hamiltonians.

PHYSICAL REVIEW LETTERS (2022)

Article Optics

Quantum control methods for robust entanglement of trapped ions

C. H. Valahu et al.

Summary: One major obstacle in practical quantum computing is achieving scalable and robust high-fidelity entangling gates. Quantum control has become an essential tool to make entangling interactions resilient to noise. This article provides a non-exhaustive summary and critical analysis of quantum control methods for achieving robust entanglement. The methods are categorized into schemes for spin or motional decoherence, and the focus is on extensions of the sigma ( x ) circle times sigma ( x ) Molmer-Sorensen interaction using microwaves and a static magnetic field gradient. The article also presents experimental realization of a proof-of-concept interaction with simultaneous robustness to spin and motional decoherence by combining various quantum control methods discussed.

JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS (2022)

Article Quantum Science & Technology

Control of Transverse Motion for Quantum Gates on Individually Addressed Atomic Qubits

M. Cetina et al.

Summary: Research shows that in trapped atomic qubits, entangling gate operations in chains can measure and suppress effects caused by laser confinement, while sympathetically trapping ancilla ions can achieve cooling throughout the entire chain.

PRX QUANTUM (2022)

Article Optics

One- and two-qubit gate infidelities due to motional errors in trapped ions and electrons

R. Tyler Sutherland et al.

Summary: In this work, analytic formulas are derived to determine the effect of error mechanisms on one-and two-qubit gates in trapped ions and electrons. The formulas consider driving field inhomogeneities, static motional frequency shifts, trap anharmonicities, field inhomogeneities, heating, and motional dephasing. The authors show that the formulas are sufficient for determining error budgets for high-fidelity gates, eliminating the need for numerical simulations in future projects.

PHYSICAL REVIEW A (2022)

Article Quantum Science & Technology

Crosstalk Suppression for Fault-tolerant Quantum Error Correction with Trapped Ions

Pedro Parrado-Rodriguez et al.

Summary: A comprehensive 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, is presented in this work. The microscopic modeling of crosstalk errors from first principles is detailed, showing the importance of using coherent vs incoherent error modeling and discussing strategies to actively suppress crosstalk at the gate level. The impact of residual crosstalk errors on the performance of fault-tolerant QEC is studied numerically, identifying the experimental target values needed to achieve beneficial QEC with low-distance topological codes in near-term trapped-ion experiments.

QUANTUM (2021)

Article Quantum Science & Technology

Software tools for quantum control: improving quantum computer performance through noise and error suppression

Harrison Ball et al.

Summary: This article introduces software tools for applying and integrating quantum control in quantum computing research, aiming to enhance the performance and capabilities of quantum computers. The tools help hardware R&D teams, algorithm developers, and end users optimize quantum logic operations and quantum algorithms with improved fault tolerance, without the need for complex logical encoding.

QUANTUM SCIENCE AND TECHNOLOGY (2021)

Article Multidisciplinary Sciences

Fault-tolerant control of an error-corrected qubit

Laird Egan et al.

Summary: Quantum error correction encodes information into a larger quantum system to protect it, and fault-tolerant circuits are essential for controlling logical qubits and suppressing errors. Experimental demonstration of fault-tolerant circuits for a Bacon-Shor logical qubit with trapped ion qubits shows significant reductions in error rates in the presence of noise. This indicates the potential of fault-tolerant circuits to enable highly accurate logical primitives in current quantum systems, with the possibility of achieving a stabilized logical qubit through improved gate operations and measurements.

NATURE (2021)

Article Physics, Multidisciplinary

High-Fidelity Bell-State Preparation with 40Ca+ Optical Qubits

Craig R. Clark et al.

Summary: This paper introduces a new variant of the light-shift scheme for entanglement generation in trapped-ion systems, and demonstrates its efficiency and stability through experimental validation, achieving a Bell state in 35 μs with high fidelity. The use of a 532 nm gate laser wavelength effectively suppresses intrinsic photon scattering errors to approximately 1 x 10(-5).

PHYSICAL REVIEW LETTERS (2021)

Article Quantum Science & Technology

Power-optimal, stabilized entangling gate between trapped-ion qubits

Reinhold Blumel et al.

Summary: Researchers have proposed a linear method to construct entangling gates on trapped-ion quantum computers. This method does not require any search in the parameter space, can achieve power-optimal gates, and can be stabilized at an arbitrary order.

NPJ QUANTUM INFORMATION (2021)

Article Multidisciplinary Sciences

High-fidelity laser-free universal control of trapped ion qubits

R. Srinivas et al.

Summary: Researchers have successfully demonstrated high-fidelity laser-free universal control of two trapped-ion qubits by utilizing microwave technology combined with radiofrequency magnetic field gradients. This technology allows for simultaneous entangling operations on multiple pairs of ions without increasing control signal power or complexity.

NATURE (2021)

Article Physics, Multidisciplinary

Efficient Stabilized Two-Qubit Gates on a Trapped-Ion Quantum Computer

Reinhold Blumel et al.

Summary: To scale up quantum processors and achieve quantum advantage, a new gate-optimizing principle has been introduced to trade off negligible amounts of gate fidelity for substantial savings in power, leading to significant increases in gate speed and/or qubit connectivity. This method has been experimentally verified on a trapped-ion quantum computer and provides increased robustness to mode drift.

PHYSICAL REVIEW LETTERS (2021)

Article Physics, Multidisciplinary

Quantum Harmonic Oscillator Spectrum Analyzers

Jonas Keller et al.

Summary: Researchers measured the noise spectrum of a quantum harmonic oscillator using its response to amplitude modulated periodic drives, demonstrating two implementations with combined sensitivity to noise. The method was successfully applied to measure the intrinsic noise spectrum of an ion trap potential.

PHYSICAL REVIEW LETTERS (2021)

Article Physics, Multidisciplinary

Quantum Oscillator Noise Spectroscopy via Displaced Cat States

Alistair R. Milne et al.

Summary: Quantum harmonic oscillators are essential for many modern quantum technologies, and a new method has been introduced to determine the frequency noise spectrum by coupling oscillator modes with a continuously driven qubit. This technique, which uses various drive patterns and data fusion routines, has successfully identified intrinsic noise in the motional frequency of a single trapped ion with high sensitivity.

PHYSICAL REVIEW LETTERS (2021)

Article Physics, Applied

Batch Optimization of Frequency-Modulated Pulses for Robust Two-Qubit Gates in Ion Chains

Mingyu Kang et al.

Summary: In trapped-ion quantum computers, two-qubit gates are generated by spin-dependent forces that entangle the internal state of the ions with their motion. This study improves the robustness of frequency-modulated Molmer-Sorensen gates to motional mode-frequency offsets through batch optimization, showing good performance up to 12 ions in numerical simulations and experimental demonstration on a two-ion chain.

PHYSICAL REVIEW APPLIED (2021)

Article Quantum Science & Technology

Frame-Based Filter-Function Formalism for Quantum Characterization and Control

Teerawat Chalermpusitarak et al.

Summary: This study introduces a theoretical framework for resource-efficient characterization and control of non-Markovian open quantum systems, which integrates experimentally motivated control capabilities and constraints. By developing a transfer filter-function formalism based on a general notion of a frame, the research overcomes important limitations of existing approaches and efficiently represents relevant control matrix elements and dynamical integrals. Specifically, it demonstrates the implementation of quantum noise spectroscopy in the presence of nonstationary noise sources and the effective achievement of control-driven model reduction for noise-optimized prediction and quantum gate design.

PRX QUANTUM (2021)

Article Physics, Applied

Phase-Modulated Entangling Gates Robust to Static and Time-Varying Errors

Alistair R. Milne et al.

PHYSICAL REVIEW APPLIED (2020)

Article Quantum Science & Technology

Numeric Optimization for Configurable, Parallel, Error-Robust Entangling Gates in Large Ion Registers

Christopher D. B. Bentley et al.

ADVANCED QUANTUM TECHNOLOGIES (2020)

Article Optics

Theory of robust multiqubit nonadiabatic gates for trapped ions

Yotam Shapira et al.

PHYSICAL REVIEW A (2020)

Article Multidisciplinary Sciences

Global entangling gates on arbitrary ion qubits

Yao Lu et al.

NATURE (2019)

Article Multidisciplinary Sciences

Parallel entangling operations on a universal ion-trap quantum computer

C. Figgatt et al.

NATURE (2019)

Article Multidisciplinary Sciences

Non-Gaussian noise spectroscopy with a superconducting qubit sensor

Youngkyu Sung et al.

NATURE COMMUNICATIONS (2019)

Article Physics, Multidisciplinary

Robust and Resource-Efficient Microwave Near-Field Entangling 9Be+ Gate

G. Zarantonello et al.

PHYSICAL REVIEW LETTERS (2019)

Article Optics

Two-qubit entangling gates within arbitrarily long chains of trapped ions

K. A. Landsman et al.

PHYSICAL REVIEW A (2019)

Article Physics, Multidisciplinary

Robust 2-Qubit Gates in a Linear Ion Crystal Using a Frequency-Modulated Driving Force

Pak Hong Leung et al.

PHYSICAL REVIEW LETTERS (2018)

Article Physics, Multidisciplinary

Robust Entanglement Gates for Trapped-Ion Qubits

Yotam Shapira et al.

PHYSICAL REVIEW LETTERS (2018)

Article Physics, Multidisciplinary

Resilient Entangling Gates for Trapped Ions

A. E. Webb et al.

PHYSICAL REVIEW LETTERS (2018)

Article Optics

Single-qubit quantum memory exceeding ten-minute coherence time

Ye Wang et al.

NATURE PHOTONICS (2017)

Article Multidisciplinary Sciences

Application of optimal band-limited control protocols to quantum noise sensing

V. M. Frey et al.

NATURE COMMUNICATIONS (2017)

Article Physics, Multidisciplinary

High fidelity quantum gates of trapped ions in the presence of motional heating

Farhang Haddadfarshi et al.

NEW JOURNAL OF PHYSICS (2016)

Article Physics, Multidisciplinary

Qubit Noise Spectroscopy for Non-Gaussian Dephasing Environments

Leigh M. Norris et al.

PHYSICAL REVIEW LETTERS (2016)

Article Physics, Multidisciplinary

High-Fidelity Universal Gate Set for 9Be+ Ion Qubits

J. P. Gaebler et al.

PHYSICAL REVIEW LETTERS (2016)

Article Physics, Multidisciplinary

Fidelity Quantum Logic Gates Using Trapped-Ion Hyperfine Qubits

C. J. Ballance et al.

PHYSICAL REVIEW LETTERS (2016)

Article Physics, Multidisciplinary

Phase-Modulated Decoupling and Error Suppression in Qubit-Oscillator Systems

Todd J. Green et al.

PHYSICAL REVIEW LETTERS (2015)

Article Physics, Multidisciplinary

Experimental noise filtering by quantum control

A. Soare et al.

NATURE PHYSICS (2014)

Article Optics

Robustness of composite pulses to time-dependent control noise

Chingiz Kabytayev et al.

PHYSICAL REVIEW A (2014)

Article Physics, Multidisciplinary

Optimal Quantum Control of Multimode Couplings between Trapped Ion Qubits for Scalable Entanglement

T. Choi et al.

PHYSICAL REVIEW LETTERS (2014)

Article Physics, Multidisciplinary

General Transfer-Function Approach to Noise Filtering in Open-Loop Quantum Control

Gerardo A. Paz-Silva et al.

PHYSICAL REVIEW LETTERS (2014)

Article Physics, Multidisciplinary

Arbitrary quantum control of qubits in the presence of universal noise

Todd J. Green et al.

NEW JOURNAL OF PHYSICS (2013)

Article Computer Science, Interdisciplinary Applications

QuTiP: An open-source Python framework for the dynamics of open quantum systems

J. R. Johansson et al.

COMPUTER PHYSICS COMMUNICATIONS (2012)

Article Physics, Multidisciplinary

Coherent Error Suppression in Multiqubit Entangling Gates

D. Hayes et al.

PHYSICAL REVIEW LETTERS (2012)

Article Optics

Dynamical decoupling sequence construction as a filter-design problem

M. J. Biercuk et al.

JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS (2011)

Article Physics, Multidisciplinary

Entanglement and Tunable Spin-Spin Couplings between Trapped Ions Using Multiple Transverse Modes

K. Kim et al.

PHYSICAL REVIEW LETTERS (2009)

Article Physics, Multidisciplinary

Ion trap quantum gates with amplitude-modulated laser beams

Christian F. Roos

NEW JOURNAL OF PHYSICS (2008)

Article Optics

Error-resistant single-qubit gates with trapped ions

N. Timoney et al.

PHYSICAL REVIEW A (2008)

Article Physics, Multidisciplinary

Arbitrary-speed quantum gates within large ion crystals through minimum control of laser beams

SL Zhu et al.

EUROPHYSICS LETTERS (2006)

Article Optics

Phase control of trapped ion quantum gates

PJ Lee et al.

JOURNAL OF OPTICS B-QUANTUM AND SEMICLASSICAL OPTICS (2005)

Article Physics, Multidisciplinary

Universal dynamical control of quantum mechanical decay: Modulation of the coupling to the continuum

AG Kofman et al.

PHYSICAL REVIEW LETTERS (2001)