Towards quantum chemistry on a quantum computer

• Published in: Nature chemistry Vol. 2; no. 2; pp. 106 - 111
• Main Authors: Lanyon, B. P., Whitfield, J. D., Gillett, G. G., Goggin, M. E., Almeida, M. P., Kassal, I., Biamonte, J. D., Mohseni, M., Powell, B. J., Barbieri, M., Aspuru-Guzik, A., White, A. G.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01-02-2010; Nature Publishing Group
• Subjects: 639/638/440; 639/638/563/758; 639/766/483/1139; 639/766/483/481; Algorithms; Analytical Chemistry; Biochemistry; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Computers; Data processing; Electrons; Hydrogen - chemistry; Inorganic Chemistry; Optical Phenomena; Organic Chemistry; Phase transitions; Physical Chemistry; Physics; Quantum computing; Quantum Theory; Simulation; Supercomputers; United States > US; Massachusetts
• ISSN: 1755-4330; 1755-4349
• DOI: 10.1038/nchem.483

Exact first-principles calculations of molecular properties are currently intractable because their computational cost grows exponentially with both the number of atoms and basis set size. A solution is to move to a radically different model of computing by building a quantum computer, which is a device that uses quantum systems themselves to store and process data. Here we report the application of the latest photonic quantum computer technology to calculate properties of the smallest molecular system: the hydrogen molecule in a minimal basis. We calculate the complete energy spectrum to 20 bits of precision and discuss how the technique can be expanded to solve large-scale chemical problems that lie beyond the reach of modern supercomputers. These results represent an early practical step toward a powerful tool with a broad range of quantum-chemical applications.
Precise calculations of molecular properties from first-principles set great problems for large systems because their conventional computational cost increases exponentially with size. Quantum computing offers an alternative, and here the H
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potential energy curve is calculated using the latest photonic quantum computer technology.