Programmable Optical Tweezer Arrays for Studying Strongly Correlated Fermions

Princeton University, Princeton NJ

Investigators

Abstract

General audience abstract: The development of materials with novel properties is a primary driver for new technologies. The behavior of the electrons in a material influences its electrical, thermal and optical properties. In particular, at low temperatures, the interplay of quantum mechanics and strong interactions between the electrons gives rise to spectacular collective phenomena. These include superconductivity (the lossless transport of electricity) as well as unusual forms of magnetism. A microscopic understanding of the physics of quantum materials is very useful in controlling their properties, but it is hindered by fundamental limitations on simulating large-scale quantum systems on classical computers. This award supports the development of a programmable analog quantum computer which can simulate electronic systems of up to a hundred particles, a task beyond the reach of even the fastest supercomputers. The analog quantum computer will consist of ultracold atoms, playing the role of the electrons, hopping and interacting in artificial crystals created with focused spots of laser light known as optical tweezers. Unlike other platforms for electronic quantum simulation, the crystal geometry is programmable in software, allowing on-demand simulations of a wide range of model electronic systems. The main outcome of the research will be a major advance in the ability to create, control, and study interacting quantum systems. The research will also train graduate and undergraduate students in the field of quantum science and prepare them for careers in industry, national labs, and academia. Technical audience abstract: The deterministic preparation, control, and readout of large ensembles of interacting quantum particles remains a frontier in modern experimental physics. Recent progress in this arena has enhanced our understanding of many-body systems and stimulated advances in quantum computing. In particular, ultracold neutral atoms in optical lattices, due to the ease of tailoring their Hamiltonians, have provided valuable insights on a wide range of topics including many-body localization, entanglement dynamics and driven many-body systems. However, two challenges have impeded quantum simulations with fermionic lattice gases from reaching their full potential: the preparation of states with entropies low enough to realize strongly-correlated phases of interest and “on-demand” reconfigurability of trapping potentials at the single-site level. This award funds the development of techniques to prepare low-entropy states of strongly-interacting fermionic atoms in programmable optical tweezer arrays, with single-site readout from quantum gas microscopy. The research will focus on realizing correlated states in one-dimensional and two-leg Fermi-Hubbard ladder systems, including interacting topological states and d-wave resonating valence bond states. This will be an important stepping stone for future work on preparing low-entropy states in 2D Hubbard tweezer arrays. 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.