An international team of researchers has found that an optical chip can simulate the motion of atoms within molecules at the quantum level, a discovery that could lead to new methods of molecular modeling and the ultimate creation of new chemicals for use as pharmaceuticals.
The team—which included scientists from Indiana University-Purdue University Indianapolis (IUPUI), the Massachusetts Institute of Technology, Nokia Bell Labs, NTT and the University of Bristol—used new methods of simulations to exploit a similarity between the vibrations of atoms in molecules and the way photons of light move in an optical chip.
Using analogies between photonics and molecular vibrations as a starting point allowed the researchers a head start in implementing intriguing simulations, which they hope to build upon and build quantum simulations and modeling tools that provide a practical advantage in the next few years.
“With this platform, in addition to vibrations of a stand-alone molecule, we are able to model the effects of environment on these quantum vibrations,” Yogesh Joglekar, study co-author and (IUPUI) School of Science physicist, said in a statement. “The chip allows us to study open quantum systems, an extremely challenging subject.”
To understand the behavior of molecules, researchers must understand how they vibrate at the quantum level. However, modeling the dynamics requires substantial computational power beyond what currently exists or even what is predicted to exist in the coming generations of supercomputers.
An optical chip, which can operate as a quantum computing circuity, uses light rather than electricity. The data from the chip allow a frame-by-frame reconstruction of atomic motions to create a virtual movie of how a molecule vibrates.
“We can think of the atoms in molecules as being connected by springs,” said University of Bristol physicist Anthony Laing, who led the project, said in a statement. “Across the whole molecule, the connected atoms will collectively vibrate, like a complicated dance routine. At a quantum level, the energy of the dance goes up or down in well-defined levels, as if the beat of the music has moved up or down a notch. Each notch represents a quantum of vibration.
“We can program a photonic chip to mimic the vibrations of a molecule mapping its components to the structure of a particular molecule, say ammonia, and then simulate how a particular vibrational pattern evolves over some time interval,” he added. “By taking many time intervals, we essentially build up a movie of the molecular dynamics.”
According to co-first author Chris Sparrow, who was a student on the project, the chip can be quickly reprogrammed to simulate different molecules.
“Because time is a controllable parameter, we can immediately jump to the most interesting points of the movie, or play the simulation in slow motion,” Sparrow said in a statement. “We can even rewind the simulation to understand the origins of a particular vibrational pattern.”
The study was published in Nature.