Physics Colloquium - Building a Quantum World with Trapped Ions

Trapped atomic ions serve as powerful quantum simulators, allowing us to build quantum worlds, i.e. models of physical systems, by manipulating their spin and motional degrees of freedom. Trapped ions can function as direct analogs in this context, or provide a set of universal quantum operations, capable of emulating arbitrary physical models through gate-based quantum circuits. Integrating such quantum computers into a network opens up new technological advancements and applications. In this colloquium we describe the transformation of an atomic physics experiment into a quantum computer and simulator. Our system is based on a chain of 171Yb+ ions with individual laser beam addressing, creating a fully connected device capable of executing any sequence of single- and two-qubit gates. This makes it an arbitrarily programmable quantum computer. Operating in a user-facility mode, we collaborate with numerous external partners to enhance its capabilities with each new application. I will present recent results, including from a hybrid lattice-gauge theory simulation, and discuss plans for expanding this approach through the utilization of a new monolithic ion-trap geometry. Additionally, we show initial results from a new quantum network experiment generating single photons on a fiber-compatible transition that are entangled with Strontium-ion qubits. We outline our vision to use this to establish a city-sized quantum network in downtown Durham, enabling the testing of innovative quantum technology applications on a quantum computer network.