Seminar

Joshua Choi - University of Virginia

Metal halide perovskites (MHPs) are revolutionizing the solar cell research field - the record power conversion efficiency of MHPs based solar cells has reached 22.7%, which rivals that of silicon solar cells. What is particularly exciting about MHPs is that they can be manufactured into solar cell devices at low-costing using low temperature solution processing. Based on these attributes, MHPs have been called the “next big thing in photovoltaics” and worldwide research efforts have grown explosively.

Eric Bittner, University of Houston

Entangled photons offer an exquisite probe to correlated dynamics within a material system. In my talk I shall discuss some recent experiments and our theoretical investigations into developing an input/output scattering theory approach that connects an incoming photon Fock state to an outgoing Fock state, treating both the internal (material) and photon dynamics on a consistent footing. As proof of concept, we show how entangled photons can probe the inner workings of a model system undergoing spontaneous symmetry breaking.

Felix Leditzky, University of Colorado, Boulder

Port-based teleportation (PBT) is a variant of the well-known task of quantum teleportation in which Alice and Bob share multiple entangled states called "ports". While in the standard teleportation protocol using a single entangled state the receiver Bob has to apply a non-trivial correction unitary, in PBT he merely has to pick up the right quantum system at a port specified by the classical message he received from Alice.

Bradley Hauer, University of Alberta

Cavity optomechanics, a field which studies the interplay between the photonic and phononic modes of an optical cavity, has seen rapid progress over the past decade. Micro/nano-scale optomechanical cavities have demonstrated potential for use in technologies such as quantum-limited metrology and transduction, as well as probes for exploring the fundamental nature of quantum mechanics.

Keysight's Quantum Engineering Toolkit: A commercial, customizable integrated control and test system

Presented by guest speaker Nizar Messaoudi, Keysight Technologies Application Engineer

With traditional classical complementary metal oxide semiconductor (CMOS) computing struggling to keep up with Moore’s law, interest in quantum computing has exploded and the University of Waterloo is at the centre of this technological revolution.

Michael Jarret, Perimeter Institute for Theoretical Physics

The runtime of Adiabatic optimization algorithms are typically characterized by the size of the spectral gap of the corresponding Hamiltonian. Gap analysis nonetheless remains a challenging problem with few general approaches.

Robin Kothari, Microsoft Research (PLEASE NOTE NEW DATE AND TIME)

We use the polynomial method to prove optimal or nearly optimal lower bounds on the quantum query complexity of several problems, resolving open questions from prior work. The problems studied include k-distinctness, image size testing, k-junta testing, approximating statistical distance, approximating Shannon entropy, and surjectivity.​ Paper available at https://arxiv.org/abs/1710.09079. This is joint work with Mark Bun and Justin Thaler.

David Layden - Massachusetts Institute of Technology (MIT)

Sensors based on quantum effects can measure various external quantities, such as magnetic fields, with high precision. Moreover, their sensitivity can scale more favourably with their size than is allowed classically — a property analogous to quantum speedups in computing. As with quantum computers, the performance of quantum sensors is limited by decoherence. Quantum error correction (QEC) has recently emerged as a promising approach to mitigate this decoherence, and therefore, to enhance sensitivity.

Xiaodong Ma: Topological insulator and the quantum anomalous Hall effect

The quantum anomalous Hall effect (QAHE) is defined as a quantized Hall effect in a system without an external magnetic field. Its physical origin relies on the intrinsic topological inverted band structure and ferromagnetism.

Peter Zoller - University of Innsbruck

We start with an overview of chiral quantum optics as quantum light-atom interfaces with broken left- right symmetry and associated quantum optical phenomena and applications. While chiral quantum optics is traditionally discussed in context of nano-photonics and nano fibers , we propose here a novel ‘free-space’ chiral quantum optics realized as atoms in free space coupled to a ‘few-atom’ quantum antenna. In particular, we discuss free space photonic quantum links between atoms (qubits) equipped with sending and receiving quantum antennas.