Events

Sangil Kwon: Phase in Superfluids and Spontaneously Broken Gauge Symmetry

It is often said that superfluids (including superconductors) can be described by a macroscopic quantum wavefunction and their phase transition can be understood based on the concept of spontaneously broken gauge symmetry. This statement is not, however, trivial at all. In this seminar, I will discuss some conceptual problems that stem from applying the concept of spontaneously broken gauge symmetry to superfluids.

IQC/Physics Special Seminar - Arghavan Safavi, University of Colorado

One of the most important goals of modern quantum sciences is to learn how to control and entangle many-body systems and use them to make powerful and improved quantum devices, materials and technologies. The challenge lies in the complexity of quantum many-body systems and the emergence of entanglement and quantum correlations.

Anqi Huang, Quantum Hacking after Measurement-Device-Independent Quantum Cryptography

Supervisor: Christopher Wilson

Thesis is on display in the Engineering graduate office, DWE 3520C. Oral defence Monday, March 26, 12:30p.m., EIT 3142.

Gilles Brassard, Université de Montréal

It is generally believed that experimental violations of Bell's inequalities (especially the recent so-called loophole-free experiments) provide evidence that quantum theory cannot be both local and realistic. We demonstrate to the contrary that all reversible-dynamics no-signalling operational theories (including unitary quantum theory) can be given a local-realistic interpretation.

Gerard Valentí Rojas - The Institute of Photonic Sciences, Spain

The laws of quantum mechanics have helped scientists to unravel the behaviour of nature at its most fundamental scales. However, quantum phenomena are often difficult to understand and simulations have historically provided a useful framework for their study. Nevertheless, when dealing with large quantum systems or real-time dynamics, the computational cost of numerical simulations can become unfeasible.

Stories of a Yale Professor turned Entrepreneur, turned Environmental Activist - what next?

Featured Speaker: Dr. Ron Dembo

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.

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.

Yoonseok Lee, University of Florida

After the discovery of topological insulators, the concept of topology permeated the various fields of condensed matter physics. Symmetry of a quantum system plays an intriguing role in close association with topology, expanding the range of topological quantum systems to superconductors/superfluids. Superfliuid 3He, which has been a prime example of symmetry breaking phase transition, is also recognized as a quantum system with various topological nature.

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.