High-Resolution Quantum Gas Microscopy of Ultracold 23Na40K Molecules Trapped in Optical Lattices

• Applicant: Dr. Carsten Robens
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: from 2019 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 421987027

The promise that quantum computers may solve problems unthinkable for any classical computer has been a leading motivation for physicists over decades to push today’s boundaries of technology further in an effort to harness simultaneously and individually the quantum properties of a large ensemble of particles. During these years, significant conceptual and technological advances have been achieved on several platforms including photons, trapped ions, ultracold atoms, superconducting qubits, and most recently Majorana fermions. However, until the present day no contender has been able to rigorously demonstrate a genuine speedup of quantum over classical devices. We here propose to build a novel multipurpose quantum hardware based on ultracold dipolar 23Na40K molecules trapped in an optical lattice. Ultracold molecules represent a radically new platform which borrows the techniques and scalability from ultracold atoms and combines it with the tunable long-range interactions of dipolar molecules. To study and control the interactions at the single molecule level we will build a molecular quantum gas microscope which remains – so far – an outstanding challenge. One of the difficulties in realizing such a molecular quantum gas microscope is to reach the required number and degeneracy of dipolar bi-alkali molecules. This in turn is limited by the efficiency at which two ultracold atoms can be converted into a so-called Feshbach molecule. We here propose a new pathway of creating molecules in their rovibrational ground state by converting Bose polarons into molecules through a stimulated rapid adiabatic passage (STIRAP). This approach holds promise to significantly enhance the conversion efficiency, potentially allowing the direct creation of a degenerate gas of ultracold molecules. After creation, we will load the ultracold 23Na40K molecules into a single layer of a three-dimensional optical lattice. A high-resolution objective will enable us to image the molecules with single lattice site resolution, thereby opening the doors to study a variety of many-body effects with long-range interaction. We further plan to demonstrate a proof of concept realization of a two-qubit gate by locally controlling the electric dipole moment of individual molecules through tightly focused laser beams. Gaining control over the quantum nature of degenerate dipolar 23Na40K molecules trapped in an optical lattice represents an epitome of a multipurpose quantum hardware ideally suited for quantum computations, quantum simulations, and precision measurements.

• DFG Programme: Research Fellowships
• International Connection: USA
• Host: Professor Dr. Martin Zwierlein