Quantum Computer Measures Energy in Molecular Hydrogen

Hydrogen Atom — Image source: The Modern Green

(PhysOrg.com) -- When it comes to measuring the properties of molecules, scientists often rely on using approximation, since quantum mechanics cannot be exactly apply to complicated situations without the use of a quantum computer. In an effort to ensure that no natural behaviors are missed, and for other purposes, scientists around the world have been working on quantum computers for decades.

And one has been built -- and used to measure molecular hydrogen.

Scientists at the University of Queensland in Brisbane, Australia, and at Harvard University, in the U.S., have built a small quantum computer capable of handling calculations on groupings of atoms that are larger than previously used. The approach to molecular simulation is described in this week's issue of Nature Chemistry.

The University of Queensland offers this in a press release on the implications of the project:

"It's very early days for quantum technology," [Andrew White, a scientist at Queensland says], "most quantum computer demonstrations have been limited to a handful of qubits. A colleague of mine in Canada says that any demonstration with less than ten qubits is cute but useless -- which makes me think of a baby with an abacus."

"However Alan [Aspuru-Guzik] and his team at Harvard have shown that when we can build circuits of just a few hundred qubits, this will surpass the combined computing power of all the traditional computers in the world, each of which uses many billions of bits."

The demonstration with the molecular hydrogen shows that it is possible to build a physical quantum computer capable of performing the kinds of calculations that we would like to be able to increase the speed of our technological advancement through a better fundamental understanding of quantum mechanics, as well as through the development of new materials.