Solidstate NMR threequbit homonuclear system for quantuminformation processing: Control and characterization
Abstract
A threequbit {sup 13}C solidstate nuclear magnetic resonance (NMR) system for quantuminformation processing, based on the malonic acid molecule, is used to demonstrate highfidelity universal quantum control via strongly modulating radiofrequency pulses. This control is achieved in the strongcoupling regime, in which the time scales of selective qubit addressing and of twoqubit interactions are comparable. State evolutions under the internal Hamiltonian in this regime are significantly more complex, in general, than those of typical liquidstate 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 threequantum 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 singlequantum dephasing data obtained using appropriate refocusing sequences. We conclude that solidstate NMR systems tailored for quantuminformation processing have excellent potential for extending the investigationsmore »
 Authors:
 Institute for Quantum Computing, University of Waterloo, Waterloo, Ontario, N2L 3G1 (Canada)
 (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; STRONGCOUPLING 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. Solidstate NMR threequbit homonuclear system for quantuminformation 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. Solidstate NMR threequbit homonuclear system for quantuminformation 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 .
"Solidstate NMR threequbit homonuclear system for quantuminformation processing: Control and characterization". United States.
doi:10.1103/PHYSREVA.73.022305.
@article{osti_20974521,
title = {Solidstate NMR threequbit homonuclear system for quantuminformation 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 threequbit {sup 13}C solidstate nuclear magnetic resonance (NMR) system for quantuminformation processing, based on the malonic acid molecule, is used to demonstrate highfidelity universal quantum control via strongly modulating radiofrequency pulses. This control is achieved in the strongcoupling regime, in which the time scales of selective qubit addressing and of twoqubit interactions are comparable. State evolutions under the internal Hamiltonian in this regime are significantly more complex, in general, than those of typical liquidstate 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 threequantum 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 singlequantum dephasing data obtained using appropriate refocusing sequences. We conclude that solidstate NMR systems tailored for quantuminformation processing have excellent potential for extending the investigations begun in the liquidstate 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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