Unlocking the Radio Sky - mapping transients and cosmic structure with novel digital telescopes

Date

Friday November 29, 2019
1:30 pm - 2:30 pm

Location

Stirling A

Matt Dobbs
McGill University Physics and CIfAR Senior Fellow

Abstract

Technology advances have opened a new era of radio observations. We are now monitoring the sky at millisecond cadence and discovering a vast catalog of new fast radio transients while simultaneously making deep maps of structure in the universe using hydrogen intensity mapping as a tracer. While these fields are still in their infancy, early results are rolling out, fuelling discovery and motivating the design for new instruments.

Engineering 2D materials with a twist

Date

Friday November 22, 2019
1:30 pm - 2:30 pm

Location

Stirling A

Cory Dean
Department of Physics, Columbia University

Abstract

Atomically thin crystals such as graphene, boron nitride and the transition metal dichalcogenides continue to attract enormous interest. Encompassing a wide range of  properties, including single-particle, topological and correlated phenomenon, these 2D materials represent  a rich class of materials in which to explore both novel physical phenomenon and new technological pursuits. By integrating these materials with one another, an exciting new opportunity has emerged in which entirely new layered heterostructures can be fabricated with emergent properties beyond those of the constituent materials. In this talk I will discuss some of our recent efforts where,  by tuning the geometry of  these heterostructures at the nanoscale, we are able to realize yet a new level of control over their electronic properties. In particular I will discuss the significant role played by the rotational alignment between adjacent layers and the approach we are taking towards manipulating this degree of freedom to dynamically tune device properties in ways that are not possible with conventional materials.

Resilient Energy-Water-Transportation Infrastructures for Smart Cities

Date

Friday November 15, 2019
1:30 pm - 2:30 pm

Location

Stirling A

Hossam Gaber
University of Ontario Institute of Technology (UOIT)

Abstract

This talk will present research planning, design and control strategies of energy-water-transportation infrastructures to support smart cities and communities. The talk will cover resiliency and performance measures to achieve smart energy, water, and transportation infrastructures using interconnected micro energy grids and mobile microgrids with hybrid energy storage systems. The talk will demonstrate modeling, control, and optimization techniques and their applications to improve the regional and global performance of energy-water-transportation infrastructures. Integrated data centers will be discussed to support the implementation in smart cities and during emergencies.

Bio

Dr. Gabbar is a full Professor in the University of Ontario Institute of Technology (UOIT) in the Faculty of Energy Systems and Nuclear Science, and cross appointed in the Faculty of Engineering and Applied Science, where he has established both the Energy Safety and Control Lab (ESCL) and Advanced Plasma Engineering Lab. He is the recipient of the Senior Research Excellence Aware for 2016, UOIT. He is leading national and international research in the areas of smart energy grids, safety and control systems, advanced plasma systems and their applications on nuclear, clean energy and production systems. He is leading research in Canada with international recognition in energy safety and control for nuclear and energy production facilities. Dr. Gabbar obtained his B.Sc. degree in 1988 with first class of honor from the Faculty of Engineering, Alexandria University (Egypt). In 2001, he obtained his Ph.D. degree from Okayama University (Japan) in the area of Safety Engineering. From 2001 till 2004, he joined Tokyo Institute of Technology (Japan), as a research associate in the area of process systems engineering. From 2004 till 2008, he joined Okayama University (Japan) as a tenured Associate Professor, in the Division of Industrial Innovation Sciences. From 2007 till 2008, he was a Visiting Professor at the University of Toronto, in the Mechanical Engineering Department.

He has more than 220 publications, including patents, books / chapters, journal and conference papers. He been invited and participated in world-known conferences and delivered plenary talks on number of scientific events and invitations to international universities. He has supervised and hosted undergraduate, graduate, postdocs, visiting researchers and scholars from different countries including: Japan, India, Qatar, Egypt, Mexico, Malaysia, China, Brazil, Chile, UAE, and Colombia.

He is finalist for the Graduate Student Supervision Excellence award in Ontario Tech University, 2019. He participated and led several large scale national and international projects, in Japan, China, Middle East, and Canada, related to smart energy grids, intelligent control systems and safety design and operation synthesis and optimization of energy systems, micro energy grids, and integrated gas-power grids. He developed novel solutions for risk-based smart energy grid design, protection, and control and hybrid energy supply systems. He proposed new integrated energy storage system based on flywheel and battery, and applied on power substations, transportation electrification, and urban infrastructures. Dr. Hossam Gaber has scholarly research in the area of smart energy grids, and control optimization of micro grid and transportation electrification technologies, and his recent book on Smart Energy Grid Engineering was published with national and international recognition. Dr. Gaber is regularly consulted and provide technical support for advanced energy systems in China, Middle East, Japan, and Canada, and invited to give lectures in number of national and international events in the area of smart energy grids. He is leading a research team for a funded project by Chinese government to design and deploy hybrid energy storage systems. He is the founding general chair of the annual IEEE Smart Energy Grid Engineering Conference, which is held in Canada.

Unmasking black holes with the Event Horizon Telescope

Date

Friday November 1, 2019
1:30 pm - 2:30 pm

Location

Stirling A

Avery Broderick
Perimeter Institute

Abstract

Black holes are, without question, one of the most bizarre and mysterious phenomena predicted by  Einstein’s theory of general relativity. They correspond to infinitely dense, compact regions in space and time, where gravity is so extreme that nothing, not even light, can escape from within.  And, their existence raises some of the most challenging questions about the nature of space and time. Over the past few decades, astronomers have identified numerous tantalizing observations that suggested that black holes are real. This past April, the search for confirmation changed dramatically with the publication of the first image ever taken of a black hole, rendering tangible what was previously only the purview of theory and science fiction. I will describe how these observations were made, how the images were generated, how quantitative measurements were obtained, and what they all mean for gravity and black hole astronomy. 

Quantum Jumps that Don’t!

Date

Tuesday October 22, 2019
3:30 pm - 4:30 pm

Location

Nanophotonics Collaboration-Lab 261A

Prof. Howard Carmichael
University of Auckland, New Zealand

Abstract

Quantum jumps are emblematic of all things quantum. Certainly that is so in the popular mind…and more than an echo from the past, "quantum jumps" still hold a prominent place in the lexicon of physics today. What, however, is the character of these "jumps" on close inspection? Discontinuous and discrete, as in Bohr’s original conception…or perhaps a version of Schrödinger’s continuous evolution, which might be "tracked", even interrupted and turned around? This seminar re-visits the jumps of single trapped ions from the mid-1980s [1] where quantum trajectory theory favours the latter option. I present the theoretical prediction and its recent experimental verification [2]: real-time monitoring tracks the jumps of an artificial atom in a superconducting circuit—the continuous path is reconstructed and the jumps interrupted and turned around.

[1] W. Nagourney et al., Phys. Rev. Lett. 56, 2797 (1986); T. Sauter et al., Phys. Rev. Lett. 57, 1696 (1986); J. C. Bergquist et al., Phys. Rev. Lett. 57, 1699 (1986).
[2] Z. K. Minev, S. O. Mundhada, S. Shankar, P. Rheinhold, R. Gutiérrez-Jáuregui, R. J. Schoelkopf, M. Mirrahimi, H. J. Carmichael, and M. H. Devoret, “To catch and reverse a quantum jump mid-flight,”  Nature 570, 200 (2019).

www.quantamagazine.org/quantum-leaps-long-assumed-to-be-instanta...

physicsworld.com/a/to-catch-a-quantum-jump/

www.quantamagazine.org/how-quantum-trajectory-theory-lets-physic...

𝕋 -operator ceilings for photonic design

Date

Friday October 18, 2019
1:30 pm - 2:30 pm

Location

Stirling A

Sean Molesky
Princeton University

Abstract:

In this presentation, we will describe how properties of the electromagnetic scattering 𝕋 -operator can be used to set absolute ceilings for any given bounding region and material on a variety of optical processes, ranging from thermal emission, scattering and absorption for propagating waves, to near-field based phenomena like radiative emission from a dipole in the presence of a plasmonic resonance and heat transfer across a nanoscale gap. 

Unifying the two overarching strategies of prior work on electromagnetic limits---modal decomposition (quasi-normal modes, Fourier and multipole expansions) and conservation principles—these 𝕋 -operator bounds are meaningfully applicable to all length scales, show a physically plausible scaling with material quality, and in the large characteristic length limit reproduce familiar ray-optics results. 

We will then discuss the usefulness of 𝕋 -operator bounds in the context of computationally driven "inverse-design" (optimization) algorithms and provide specific examples of structures that nearly reach the performance limit set by our analysis.

Planets Big and Small

Date

Friday October 4, 2019
1:30 pm - 2:30 pm

Location

Stirling A

Eve Lee
McGill University

Abstract:

From gas-poor Earths to gas-rich Jupiters, planets come in a variety of sizes. I will describe the physics behind the diversity of exoplanets---how the core and gas assembly processes give rise to the observed distribution of radii and orbital periods. Basic astrophysical considerations of gas dynamical friction, gravitational scattering, collisional mergers, and gas accretion by cooling inform us that planets smaller than Neptune likely emerged in situ, in the late stages of disk evolution. Larger planets on the other hand must have nucleated from massive cores that assemble in the early stages of disk evolution. I will show how the theory of star-disk-planet interaction can describe the observed planet occurrence rate as it varies across orbital periods, planet radii, and stellar metallicities.

Modern Al(radio)chemistry to cure cancer

Date

Friday September 20, 2019
1:30 pm - 2:30 pm

Location

Stirling A

Prof. Valery Radchenko
Research Scientist at TRIUMF
Adjunct professor at UBC Chemistry

Abstract

The use of radionuclides has become more and more common in the diagnosis and therapy of cancer. Targeted radionuclide diagnostics and therapy based on the combination of appropriate radionuclides with selective delivery systems (e.g. antibody, peptides etc.) maximizes precision of the imaging as well as minimizes the damage of healthy tissues during therapy. Furthermore, based on imaging (tumor sizes and locations), appropriate therapeutic radionuclides emitting alpha, beta- particles or auger electrons can be utilized. After production, in most cases, medical radionuclides need to be isolated from the target material and preconditioned for further radiopharmaceutical application.

Appropriate bifunctional chelator systems should be in place to effectively attach some of the radionuclides (e.g. radiometals) to biomolecules.

Several examples of production strategies of medical radionuclides with relation to TRIUMF facilities will be presented.

Computational Modelling of Silicon Phononic Crystals

Date

Wednesday June 26, 2019
10:30 am - 11:30 am

Location

Stirling 401

Prof. Ralf Meyer
SHARCNET Research Chair,
Department of Mathematics and Computer Science,
Laurentian University

Abstract

Phononic crystals are periodically structured, synthetic materials that allow control of the propagation of elastic waves. Through the choice of the parameters of the periodic structuring opens the phonon dispersion relations can be modified and vibrational band gaps can be created. Phononic crystals have numerous potential applications in areas such as noise control, ultrasound imaging and telecommunications. Since the principal carriers of heat in non-metallic materials are phonons, nanoscale phononic crystals with operating frequencies in the THz regime can be utilized to control the flow of heat. This has potential applications in energy harvesting and novel heating or cooling technologies.

In this work, molecular dynamics simulations and finite element computational are used to study the vibrational band structure and thermal resistance of silicon phononic crystals. The results show how a binary honeycomb lattice can be used to selectively control the size of the lowest vibrational band gap. The thermal resistance of the model systems is determined with the help of Reverse Non-Equilibrium Molecular Dynamics (RNEMD). The results show differences in the scaling behaviour of the thermal resistance for phononic crystals and nanowires. 

Progress in Reactive Printing of Self Assembled Materials and Melt Spinning of Flexible Silicon

Date

Friday April 5, 2019
1:30 pm - 2:30 pm

Location

Stirling A

Ghassan Jabbour
Professor and holder of the Canada Research Chair in Engineered Advanced Materials and Devices,
University of Ottawa

Abstract

Perhaps some of the most important and urgent Grand Challenges facing the inhabitants of this earth which need our immediate attention are: 1) Energy, 2) Water, and 3) Food Resources. Although the intention was not to place “energy” as the top challenge, in many respects the latter two cannot be addressed successfully on a wider and more accessible scale without low cost and low power consumption approaches to their production.  One of our research themes focuses on developing and implementing environmentally friendly processing and device testing approaches. The target is to realize sustainable development and manufacturing of multi-scale functional materials, devices and systems, for applications in areas including, but not limited to, power generation, solid-state-lighting, energy conversion and storage, and light weight alloys. Throughout the research, efforts are made to eliminate as many energy-demanding processing steps as possible, without sacrificing device performance or materials specifications. In this venue, I will review our advances on two of our research topics aiming at preparing the foundational work for their low-cost R2R manufacturing:

  1. Reactive Printing Fabrication of self-assembled nanoparticles and quantum dots, and
  2. Melt spinning approach to flexible silicon substrates.