Observing the quantum topology of light

Area of Science:

• Quantum optics
• Condensed matter physics
• Topological photonics

Background:

• Topological photonics leverages classical degrees of freedom for topological light modes.
• The quantum nature of light offers distinct topological states beyond classical topology.
• Superconducting circuits provide a platform for exploring quantum phenomena.

Purpose of the Study:

• To implement experiments on topological states of quantized light.
• To construct one- and two-dimensional Fock-state lattices in a superconducting circuit.
• To explore rich topological physics in the quantum regime of light.

Main Methods:

• Utilizing superconducting circuits to create quantum topological states.
• Constructing one- and two-dimensional Fock-state lattices.
• Experimental realization of topological phenomena in quantized light.

Main Results:

• Demonstrated topological zero-energy states of the Su-Schrieffer-Heeger model.
• Observed strain-induced pseudo-Landau levels.
• Realized the valley Hall effect and Haldane chiral edge currents in quantized light.

Conclusions:

• Extended topological states of light into the quantum regime.
• Bridged topological phases in condensed-matter physics with circuit quantum electrodynamics.
• Enabled control over quantum states in multiple resonators.