Simulating Spins with an Array of Single Molecules

General audience abstract:

Quantum mechanics is at the heart of countless scientific problems, from the detailed behavior of molecules to superconductivity to microelectronics to lasers. The simplest quantum mechanical behavior has already been used to build the precise atomic clocks at the heart of our Global Positioning System, which underlies the smartphone maps that most Americans use for navigation.

The current project funds a study of more complex quantum behavior, where many quantum systems interact in a precisely controlled manner. As moderately-sized interacting quantum systems are beyond the prediction power of even the world’s fastest supercomputers, such “quantum simulators” are thought to offer new insights that may advance chemistry, physics, medicine, and energy technology.

The systems developed here, based on individually controlled interacting molecules, will also strengthen American leadership in the world-wide pursuit of quantum technologies and train and prepare students for the quantum technology workforce. Technical audience abstract:

Quantum simulation, where phase diagrams and dynamics of many-body quantum systems can be simulated directly by precisely controlled laboratory analogues, has generated much interest in the Atomic, Molecular and Optical Physics (AMO) community. Platforms for quantum simulation abound and have already seen success in studying quantum magnetism, many-body localization, the Fermi-Hubbard model, and topological phases.

Fully controlled systems of ultracold molecules, with their rich internal structure and long-range electric dipole interactions, have been proposed as candidates to add to these platforms in simulating the dynamics of spin systems, among many others. This project aims to create a quantum simulator of spin dynamics consisting of a configurable array of ultracold dipolar molecules, assembled atom by atom and held in individual optical tweezers.

The work involves expanding full quantum state control of a single molecule to an array of molecules and tuning their inter-particle interactions by electric field and microwave control. Furthermore, a combination of optical tweezers and lattices to simultaneously reduce photon scattering while allowing uniform trapping potentials, high trapping frequencies, flexible geometries, and a fast repetition rate will be pursued.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.