Physicists observe behavior of quantum materials in curved space Light and matter are typically viewed as distinct entities that follow their own, unique rules. Matter has mass and typically exhibits interactions with other matter, while light is massless and does not interact with itself. Yet, wave-particle duality tells us that matter and light both act sometimes like particles, and sometimes like waves. In work published online this week in the journal Nature, Simon's group presents new experimental observations of a quantum Hall material near a singularity of curvature in space. Read more at: http://phys.org/news/2016-06-physicists-behavior-quantum-materials-space.html#jCp
http://www.nature.com/nature/journal/vaop/ncurrent/full/nature17943.html Synthetic Landau levels for photons Synthetic photonic materials are an emerging platform for exploring the interface between microscopic quantum dynamics and macroscopic material properties1, 2, 3, 4, 5. Photons experiencing a Lorentz force develop handedness, providing opportunities to study quantum Hall physics and topological quantum science6, 7, 8. Here we present an experimental realization of a magnetic field for continuum photons. We trap optical photons in a multimode ring resonator to make a two-dimensional gas of massive bosons, and then employ a non-planar geometry to induce an image rotation on each round-trip9. This results in photonic Coriolis/Lorentz and centrifugal forces and so realizes the Fock–Darwin Hamiltonian for photons in a magnetic field and harmonic trap10. Using spatial- and energy-resolved spectroscopy, we track the resulting photonic eigenstates as radial trapping is reduced, finally observing a photonic Landau level at degeneracy. To circumvent the challenge of trap instability at the centrifugal limit10, 11, we constrain the photons to move on a cone. Spectroscopic probes demonstrate flat space (zero curvature) away from the cone tip. At the cone tip, we observe that spatial curvature increases the local density of states, and we measure fractional state number excess consistent with the Wen–Zee theory, providing an experimental test of this theory of electrons in both a magnetic field and curved space12, 13, 14, 15. This work opens the door to exploration of the interplay of geometry and topology, and in conjunction with Rydberg electromagnetically induced transparency, enables studies of photonic fractional quantum Hall fluids16, 17 and direct detection of anyons
