In a groundbreaking scientific achievement, researchers have ventured into the quantum realm to directly observe a molecular phenomenon vital to fundamental chemical reactions like photosynthesis. They accomplished this remarkable feat by employing a quantum computer to decelerate a chemical reaction to an astonishing extent—a staggering slowdown of 100 billion times the reaction’s natural pace.
This groundbreaking study, featured in the journal Nature Chemistry on August 28, revolves around a molecular interaction called a “conical intersection.” These intersections are pivotal points in the molecular geometry where the energy levels between two surfaces are perfectly balanced. They serve as conduits between electronic states, facilitating rapid transitions that propel chemical reactions forward. Conical intersections play a role in numerous reactions, including the everyday processes of photosynthesis and light detection within the retina.
The swiftness of these reactions had previously made it impossible for scientists to directly observe a conical intersection in action. To overcome this hurdle, researchers at the University of Sydney harnessed the power of a trapped-ion quantum computer—a device capable of confining quantum particles in electric fields and manipulating them using lasers.
“In nature, the whole process is over within femtoseconds,” remarked Vanessa Olaya Agudelo, a co-author of the study and a doctoral student in chemistry. “That’s a billionth of a millionth—or one quadrillionth—of a second. Using our quantum computer, we built a system that allowed us to slow down the chemical dynamics from femtoseconds to milliseconds.”
This groundbreaking slowdown enabled researchers to obtain meaningful measurements of the reaction as it unfolded.
Christophe Valahu, a physicist at the University of Sydney and a co-author of the study, emphasized, “Our experiment wasn’t a digital approximation of the process—this was a direct analog observation of the quantum dynamics unfolding at a speed we could observe.”
Understanding these ultrafast dynamics holds the promise of providing fresh insights into various chemical reactions with broad applications.
Vanessa Olaya Agudelo expressed, “It is by understanding these basic processes inside and between molecules that we can open up a new world of possibilities in materials science, drug design, or solar energy harvesting. It could also help improve other processes that rely on molecules interacting with light, such as how smog is created or how the ozone layer is damaged.”
This groundbreaking research showcases the potential of quantum computing to unlock the mysteries of the quantum world, offering unprecedented insights into the fundamental processes that shape our chemical universe.