Building Topological Quantum Matter in Superconducting Wire Arrays
We utilize a notion of "combinatorial gauge symmetry", where the gauge symmetry involves not just local rotations of spins, but also permutations of spins. This allows the construction of exact gauge invariant Hamiltonians using just two-body interactions. Models constructed in this way include the toric code and any Abelian and Non-Abelian generalization. New models also emerge in this paradigm. An advantage of the exact symmetry: the topological energy gaps need not be limited to a perturbative regime, but could potentially persist for a wider range of parameters.
Automated Distribution of Entanglement in New York City / Discussion of Startup Life
In the first half of this talk, I'll discuss Qunnect's approach to quantum networking based on warm-atomic ensembles. I'll introduce some of the devices that we build to distribute entanglement over long distances, and experiments we've performed on our GothamQ testbed in New York City. In the second half I'll talk about what it's like to work at a startup, and welcome audience questions on the topic.
Tunable Topology and Correlated States in Twisted Homobilayer Transition Metal Dichalcogenides
Abstract: We create honeycomb superlattice structures in TMD moiré materials as model systems to
study magnetism, electronic correlations and topology. In twisted MoTe 2 , we realize topological flat
bands that closely resemble the lowest Landau level but in the absence of an external magnetic field.
We present evidence for integer and fractional Chern states [1], which are the lattice analogues of
integer and fractional quantum Hall states at zero magnetic field. We further explore correlated states in
Bright Soliton Pulse Pairs in High-Q Thin-Film Si3N4 Microresonators
Abstract: Optical microresonators can trap light within compact volumes at discrete resonant frequencies, and soliton microcombs have advanced the miniaturization of various comb systems. Thin-film silicon nitride (Si3N4) microresonators, fabricated using CMOS foundry techniques, possess high-Q factors and have demonstrated many applications towards photonic integration. However, this platform has traditionally struggled to support bright solitons due to its normal dispersion nature.
No switch, no limit – Diffraction-unlimited imaging of multiple point scatterers
Abstract: From bio-physics to quantum simulators, many fields depend on sub-diffraction imaging of multiple point sources.
Collective light scattering in cold atomic ensembles: super-radiance, driven Dicke model and correlations
Abstract: This talk will present our work on the observation of super-radiance in a cloud of cold atoms driven by a laser. We start from an elongated cloud of laser cooled atoms that we excite either perpendicularly or along its main axis. This situation bears some similarities with cavity quantum electrodynamics: here the cavity mode is replaced by the diffraction mode of the elongated cloud. We observe superradiant pulses of light after population inversion.
Universal dynamics of nonequilibrium quantum matter
Abstract: Today’s programmable quantum simulators offer versatile platforms for exploring many-body phases and dynamics in correlated quantum systems. In this talk, we present some new—and surprising—insights into nonequilibrium quantum dynamics inspired by such recent experimental advances. First, we focus on understanding the evolution of closed quantum systems driven through a phase transition, which is crucial for quantum state preparation and adiabatic algorithms.
Microscopic and Emergent Dynamics of Quantum Information Flows
Abstract: The past fifty years of scientific and technological progress have clearly highlighted information as a physical resource - one that can be traded for heat, work, and other energetic resources. With the ongoing new wave of quantum-based technologies, understanding the microscopic and emergent dynamics of quantum information in many-body quantum systems has thus become a priority.
Macroscopic quantum motion of a nanogram-scale object
Abstract: I will describe measurements of individual phonons in a 1 ng body of superfluid helium. When this body is in equilibrium, its phonon correlations are consistent (up to 4th order) with a thermal state of mean occupancy ~ 1. This purity is preserved even when the mode is driven to a coherent state with an amplitude corresponding to ~100,000 phonons. I will describe how these results can be used to constrain nonlinear extensions of quantum mechanics, and to distribute entanglement over kilometer-scale optical fiber networks.
Controlling light down to the single-photon level with integrated quantum photonic devices
Abstract: Light-matter interactions allow adding functionalities to photonic on-chip devices, thus enabling developments in classical and quantum light sources, energy harvesters and sensors. These advances have been facilitated by precise control in growth and fabrication techniques that have opened new pathways to the design and realization of semiconductor devices where light emission, trapping and guidance can be efficiently controlled at the nanoscale.