Cavity-Enhanced Optical Lattices for Scaling Neutral Atom Quantum Technologies to Higher Qubit Numbers

We demonstrate a cavity-based solution to scale up experiments with ultracold atoms in optical lattices by an order of magnitude over state-of-the-art free-space lattices. Our two-dimensional (2D) optical lattices are created by power-enhancement cavities with large mode waists of 489(8)μm and allow us to trap ultracold strontium atoms at a lattice depth of 60μK by using only 80mW of input light per cavity axis. We characterize these lattices using high-resolution clock spectroscopy and resolve carrier transitions between different vibrational levels. With these spectral features, we locally measure the lattice potential envelope and the sample temperature with a spatial resolution limited only by the optical resolution of the imaging system. The measured ground-band and trap lifetimes are 18(3)s and 59(2)s, respectively, and the lattice frequency (depth) is long-term stable on the megahertz (0.1%) level. Our results show that large, deep, and stable 2D cavity-enhanced lattices can be created at any wavelength and can significantly increase the qubit number for neutral-atom-based quantum simulators, quantum computers, sensors, and optical-lattice clocks