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Simulated Quantum Computation of Molecular Energies
Science (2005)
  • Alan Aspuru-Guzik, Harvard University
  • Anthony D. Dutoi, University of the Pacific
  • Peter Love, Haverford College
  • Martin Head-Gordon, University of California, Berkeley
The calculation time for the energy of atoms and molecules scales exponentially with system size on a classical computer but polynomially using quantum algorithms. We demonstrate that such algorithms can be applied to problems of chemical interest using modest numbers of quantum bits. Calculations of the water and lithium hydride molecular ground-state energies have been carried out on a quantum computer simulator using a recursive phase-estimation algorithm. The recursive algorithm reduces the number of quantum bits required for the readout register from about 20 to 4. Mappings of the molecular wave function to the quantum bits are described. An adiabatic method for the preparation of a good approximate ground-state wave function is described and demonstrated for a stretched hydrogen molecule. The number of quantum bits required scales linearly with the number of basis functions, and the number of gates required grows polynomially with the number of quantum bits.
Publication Date
September 9, 2005
Citation Information
Alan Aspuru-Guzik, Anthony D. Dutoi, Peter Love and Martin Head-Gordon. "Simulated Quantum Computation of Molecular Energies" Science Vol. 309 Iss. 5741 (2005) p. 1704 - 1707 ISSN: 0036-8075
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