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Title: Solid-state NMR three-qubit homonuclear system for quantum-information processing: Control and characterization

Abstract

A three-qubit {sup 13}C solid-state nuclear magnetic resonance (NMR) system for quantum-information processing, based on the malonic acid molecule, is used to demonstrate high-fidelity universal quantum control via strongly modulating radio-frequency pulses. This control is achieved in the strong-coupling regime, in which the time scales of selective qubit addressing and of two-qubit interactions are comparable. State evolutions under the internal Hamiltonian in this regime are significantly more complex, in general, than those of typical liquid-state NMR systems. Moreover, the transformations generated by the strongly modulating pulses are shown to be robust against the types of ensemble inhomogeneity that dominate in the employed molecular crystal system. The secondary focus of the paper is upon detailed characterization of the malonic acid system. The internal Hamiltonian of the qubits is determined through spectral simulation. A pseudopure state preparation protocol is extended to make a precise measurement of the dephasing rate of a three-quantum coherence state under residual dipolar interactions. The spectrum of intermolecular {sup 13}C-{sup 13}C dipolar fields in the crystal is simulated, and the results compared with single-quantum dephasing data obtained using appropriate refocusing sequences. We conclude that solid-state NMR systems tailored for quantum-information processing have excellent potential for extending the investigationsmore » begun in the liquid-state systems to a greater number of qubits.« less

Authors:
; ; ; ; ; ;  [1];  [2]
  1. Institute for Quantum Computing, University of Waterloo, Waterloo, Ontario, N2L 3G1 (Canada)
  2. (United States)
Publication Date:
OSTI Identifier:
20974521
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevA.73.022305; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CARBON 13; HAMILTONIANS; INTERACTIONS; LIQUIDS; MALONIC ACID; MOLECULAR CRYSTALS; MOLECULES; NUCLEAR MAGNETIC RESONANCE; QUANTUM COMPUTERS; QUANTUM MECHANICS; QUBITS; SIMULATION; SOLIDS; SPECTRA; STRONG-COUPLING MODEL; TRANSFORMATIONS

Citation Formats

Baugh, Jonathan, Moussa, Osama, Ryan, Colm A., Laflamme, Raymond, Ramanathan, Chandrasekhar, Havel, Timothy F., Cory, David G., and Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139. Solid-state NMR three-qubit homonuclear system for quantum-information processing: Control and characterization. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.022305.
Baugh, Jonathan, Moussa, Osama, Ryan, Colm A., Laflamme, Raymond, Ramanathan, Chandrasekhar, Havel, Timothy F., Cory, David G., & Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139. Solid-state NMR three-qubit homonuclear system for quantum-information processing: Control and characterization. United States. doi:10.1103/PHYSREVA.73.022305.
Baugh, Jonathan, Moussa, Osama, Ryan, Colm A., Laflamme, Raymond, Ramanathan, Chandrasekhar, Havel, Timothy F., Cory, David G., and Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139. Wed . "Solid-state NMR three-qubit homonuclear system for quantum-information processing: Control and characterization". United States. doi:10.1103/PHYSREVA.73.022305.
@article{osti_20974521,
title = {Solid-state NMR three-qubit homonuclear system for quantum-information processing: Control and characterization},
author = {Baugh, Jonathan and Moussa, Osama and Ryan, Colm A. and Laflamme, Raymond and Ramanathan, Chandrasekhar and Havel, Timothy F. and Cory, David G. and Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139},
abstractNote = {A three-qubit {sup 13}C solid-state nuclear magnetic resonance (NMR) system for quantum-information processing, based on the malonic acid molecule, is used to demonstrate high-fidelity universal quantum control via strongly modulating radio-frequency pulses. This control is achieved in the strong-coupling regime, in which the time scales of selective qubit addressing and of two-qubit interactions are comparable. State evolutions under the internal Hamiltonian in this regime are significantly more complex, in general, than those of typical liquid-state NMR systems. Moreover, the transformations generated by the strongly modulating pulses are shown to be robust against the types of ensemble inhomogeneity that dominate in the employed molecular crystal system. The secondary focus of the paper is upon detailed characterization of the malonic acid system. The internal Hamiltonian of the qubits is determined through spectral simulation. A pseudopure state preparation protocol is extended to make a precise measurement of the dephasing rate of a three-quantum coherence state under residual dipolar interactions. The spectrum of intermolecular {sup 13}C-{sup 13}C dipolar fields in the crystal is simulated, and the results compared with single-quantum dephasing data obtained using appropriate refocusing sequences. We conclude that solid-state NMR systems tailored for quantum-information processing have excellent potential for extending the investigations begun in the liquid-state systems to a greater number of qubits.},
doi = {10.1103/PHYSREVA.73.022305},
journal = {Physical Review. A},
number = 2,
volume = 73,
place = {United States},
year = {Wed Feb 15 00:00:00 EST 2006},
month = {Wed Feb 15 00:00:00 EST 2006}
}
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