Researchers at Yale, Google, and the University of California-Santa Barbara have created a device that simulates the quantum "tunneling" behavior of protons that occurs in chemistry, a process so common it occurs in everything from photosynthesis to the formation of human DNA.
The advance has the potential to aid researchers across a variety of disciplines, including the development of new solar fuels, pharmaceuticals, and materials. It is described in a new study in the journal PRX Quantum.
Quantum tunneling is a mechanism by which particles, such as electrons or protons, pass through an energy barrier they should not have sufficient energy to cross.
"Our system is so clean and controllable that we could resolve very subtle quantum tunneling effects with it that were unknown to us," said co-first author Rodrigo Cortiñas, a former Yale postdoctoral researcher who is now at Google Quantum AI in Santa Barbara, California. "This experiment taught us things that can matter in chemical systems."
The paper's other co-first authors are Max Schäfer, a former Yale graduate student now at the University of California-Santa Barbara, and Alejandro Cros Carrillo de Albornoz, a former visiting researcher at Yale.
In DNA, protons can shift between positions within a base pair - base pairs are the building blocks of the DNA double helix structure - via a process called quantum tunneling. It is a process with no counterpart in classical physics, but it is known to be influenced by certain aspects of the structure where it occurs, such as barrier height and asymmetry.
For the new study, the researchers built a superconducting quantum circuit that recreates the structures found in chemistry and allows the user to adjust the device's barrier height and asymmetry.
