Quantized topological energy pumping and Weyl points in Floquet synthetic dimensions with a driven-dissipative photonic molecule

TL;DR

This paper demonstrates how a driven-dissipative photonic molecule can exhibit quantized topological energy pumping and Weyl points in Floquet synthetic dimensions, enabling higher-dimensional topological effects and Hamiltonian engineering.

Contribution

It introduces a novel photonic platform that leverages dissipation and multiple drives to observe topological pumping and Weyl points in synthetic dimensions.

Findings

Enhanced topological energy pumping due to dissipation

Realization of Weyl points and measurement of Berry curvature

Direct engineering of Hamiltonians in k-space using modulation

Abstract

Topological effects manifest in a wide range of physical systems, such as solid crystals, acoustic waves, photonic materials and cold atoms. These effects are characterized by `topological invariants' which are typically integer-valued, and lead to robust quantized channels of transport in space, time, and other degrees of freedom. The temporal channel, in particular, allows one to achieve higher-dimensional topological effects, by driving the system with multiple incommensurate frequencies. However, dissipation is generally detrimental to such topological effects, particularly when the systems consist of quantum spins or qubits. Here we introduce a photonic molecule subjected to multiple RF/optical drives and dissipation as a promising candidate system to observe quantized transport along Floquet synthetic dimensions. Topological energy pumping in the incommensurately modulated photonic molecule is enhanced by the driven-dissipative nature of our platform. Furthermore, we provide a path to realizing Weyl points and measuring the Berry curvature emanating from these reciprocal-space ($k$-space) magnetic monopoles, illustrating the capabilities for higher-dimensional topological Hamiltonian simulation in this platform. Our approach enables direct $k$-space engineering of a wide variety of Hamiltonians using modulation bandwidths that are well below the free-spectral range (FSR) of integrated photonic cavities.