Two-dimensional lattice gauge theories with superconducting quantum circuits

Area of Science:

• Quantum Simulation
• Condensed Matter Physics
• High-Energy Physics

Background:

• Quantum simulators offer a platform for studying complex quantum systems.
• Lattice gauge theories and quantum dimer models exhibit rich phases like spin liquids and confinement.
• Investigating these models is computationally challenging for classical computers.

Purpose of the Study:

• To demonstrate the implementation of quantum simulations for lattice gauge theories using superconducting circuits.
• To explore confined/deconfined phases in quantum link models and spin liquid/valence bond solid phases in quantum dimer models.
• To investigate fractionalized strings and quantum phase transition dynamics.

Main Methods:

• Utilizing state-of-the-art superconducting circuit technology with superconducting qubits.
• Exploiting strong non-linear couplings between quantized excitations.
• Engineering gauge-invariant Hamiltonians, including ring-exchange and four-body Ising interactions.

Main Results:

• Successful simulation of quantum phenomena in relatively small superconducting circuit lattices.
• Demonstration of investigating electric flux string dynamics, indicating confinement in gauge invariant field theories.
• Observation of these phenomena despite decoherence and disorder effects.

Conclusions:

• Superconducting circuits provide a viable platform for simulating complex quantum phenomena.
• Minimal circuit instances can reveal key properties of gauge theories and condensed matter models.
• Larger-scale realizations could tackle currently intractable problems in physics.