Emergence and Frustration of Magnetism with Variable-Range Interactions in a Quantum Simulator
PFC researchers explored how to frustrate a quantum magnet comprised of sixteen atomic ions – to date the largest ensemble of qubits to perform a simulation of quantum matter.
Physicists engineer a quantum magnet using lasers and ion qubits.Each ion has two internal energy states that make up a qubit. Laser beams can manipulate the Coulomb force to create tunable, long range magnetic-like interactions, where each ion qubit represents a tiny magnet.
With the turn of some knobs (laser frequencies), the team can induce and vary antiferromagnetic interactions. The crystal can easily form various antiferromagnetic combinations, instead of the simple nearest neighbor antiferromagnet (up down up down). In fact, with a few technical upgrades, the researchers can potentially engineer situations where the magnets can reside in an exponentially large number of antiferromagnetic states, generating massive quantum entanglement that accompanies this frustration.
The ability of adjust the range of the interaction is unavailable in real materials. This type of simulation could therefore help in the design of new types of materials that possess exotic properties, with potential applications to electrical transport, sensors, or transducers.