Washington: In a groundbreaking approach, scientists have used a quantum computer to calculate the precise energy of molecular hydrogen, which could have profound implications not just for quantum chemistry, but also for a range of fields from cryptography to materials science.
The work comes from a partnership between a team of theoretical chemists at Harvard University and a group of experimental physicists led by Andrew White at the University of Queensland in Brisbane, Australia.
“One of the most important problems for many theoretical chemists is how to execute exact simulations of chemical systems,” said lead researcher Alan Aspuru-Guzik, assistant professor of chemistry and chemical biology at Harvard University.
“This is the first time that a quantum computer has been built to provide these precise calculations,” he added.
Aspuru-Guzik’s team coordinated experimental design and performed key calculations, while his partners in Australia assembled the physical “computer” and ran the experiments.
While a number of other physical systems could serve as a computer framework, Aspuru-Guzik’s colleagues in Australia used the information encoded in two entangled photons to conduct their hydrogen molecule simulations.
Each calculated energy level was the result of 20 such quantum measurements, resulting in a highly precise measurement of each geometric state of molecular hydrogen.
“This approach to computation represents an entirely new way of providing exact solutions to a range of problems for which the conventional wisdom is that approximation is the only possibility,” said Aspuru-Guzik. Ultimately, the same quantum computer that could transform Internet cryptography could also calculate the lowest energy conformations of molecules as complex as cholesterol.Quantum computing has been heralded for its potential to solve certain types of problems that are impossible for conventional computers to crack.
First Published: Monday, January 11, 2010, 16:24