Chemical and Condensed Matter Physics

Chemical and Condensed Matter Physics

Chemical and Condensed Matter Physicists study very large collections of atoms or molecules in which the interactions between constituents are strong. Solids and liquids are prime examples, within which interactions are governed by electric and magnetic fields. Given the potential for practical applications, many researchers engage in the development and characterization of new materials. Technologically important processes include conduction in metals, non-conduction in insulators, and semiconduction, the explanations for which require an understanding of the behaviour of matter in the quantum realm.

Here are the researchers in Chemical and Condensed Matter Physics who are able to supervise graduate students. To see a detailed profile of anyone, including contact information, click on the title bar or portrait. To see a personal research website (if available), click on the research picture.

Nanophotonics and materials for solar energy and biosensing applications.

Our research focuses on the materials and physical chemistry of nanostructures with potential applications ranging from solar energy conversion to bio-sensing. In particular, we are interested in synthesizing and assembling nanomaterials into 3D and 2D structures via a combination of bottom-up approach and top-down lithographic technique to derive novel optical, electrical, and chemical properties. We employ a wide range of characterization methods and various optical spectroscopies to elucidate the interplay between material properties and functions.

Computational chemistry, especially applications to atomic clusters, molecular ions, and transition metal complexes.

Using various methods of computational chemistry in combination with global optimization and simulation methods, I study atomic clusters that range in size from 3 atoms to a few hundred atoms. The geometric structure and properties of small clusters are very different from those of the corresponding bulk materials. For example, silver clusters are not fragments of the fcc crystal, and clusters of rhodium are magnetic. Our theoretical predictions of vibrational spectra and electron detachment energies are compared to experiment for structure elucidation. We try to understand the factors controlling stability, so that we might predict cluster sizes and compositions that are particularly stable. We also model surfaces and noncrystalline materials with clusters having a hundred or more atoms using more approximate theoretical models, such as empirical potentials and model hamiltonians. I am also interested in molecular ions and transition metal complexes.

Molecular mechanisms of biological processes and disease; Cell biology, including stem cells; Drug screening; Biophysical, biomedical, and bioanalytical techniques.

I focus on understanding the molecular mechanisms of diseases, especially cancer, neurodegenerative disorders and immune disorders. To that end, my group and I develop new biophysical and bioanalytical approaches for studying and separating the chemical contents of individual cells, particularly proteins, enzymes, and DNA. We are also interested in understanding the molecular mechanisms that govern the fate of stem cells. Specifically, methods of chemical analysis are combined with advanced techniques in cell biology such as fluorescence image cytometry to study the molecular mechanisms of fundamental biological processes (cell cycle, cell differentiation, and apoptosis).

Micro- and nano-structuring of polymer material systems; Bio-based and smart multifunctional materials; Advanced thermal management materials.

My research is focussed on micro- and nano-structuring of polymer material systems, with the emphasis on tailoring and optimizing their multifunctional properties for a wide spectrum of applications (e.g., energy storage and harvesting, sensing and actuation, biomedical devices, thermal management, and environmentally benign packaging). This highly interdisciplinary research area requires integrating the principles and techniques of advanced manufacturing, materials science, fluid mechanics, thermodynamics, and rheological sciences.

Surface science; Thin films; Preparation and characterization of novel nanomaterials and devices.

My research aims at creating new thin films and nanostructured materials that possess interesting properties that can be used as sensors, solar energy harvesting devices, and electronic components. Ultimately our research goals are to understand the formation of these materials and to relate their structures and morphology to their electrochemical/electronic, catalytic or/and magnetic properties. These studies are critical for implementing thin film and nanostructure technologies because the surface and interface effects often dominate and alter significantly familiar bulk properties in these low dimensionality systems. In search of novel film materials, our work has focussed on the exploration of electro-deposited thin films and nanostructures as well as the use of efficient surface modification methods such as formation of alkanethiol self-assembled monolayers and the hydrosilylation reaction to incorporate relevant functionalities at gold and hydrogen-terminated silicon surfaces, respectively. The latter can be employed as platforms for Matrix Assisted Laser Desorption and Ionization Mass Spectrometry (MALDI MS) analysis. The implementation of surface-sensitive techniques outside vacuum, such as surface X-ray scattering, scanning tunnelling microscopy (STM), or atomic force microscopy (AFM), provides new knowledge on the structure and morphology of these low dimensionality materials. We also use other surface-sensitive methods such as Attenuated Total Reflectance FTIR (ATR FTIR) and X-ray photoelectron spectroscopy (XPS), to characterize these materials.

All of our research projects deal in one way or another with low dimensionality systems and the importance of changes in material properties due to the creation or presence of interfaces. We are currently engaged in several projects: (a) the investigation of the effect that dye functionalities and novel hole transport materials have on solar cell responses in dye-sensitized solar cells; (b) the study of the formation of epitaxial bismuth on conductors and semiconductors; (c) the growth and characterization of ternary alloy semiconductors on nanoporous films; (d) dye adsorption processes at well-defined semiconductor surfaces; (e) surface modifications for the creation of functional surfaces for tissue imaging. Collaboratively, we have engaged in the characterization of systems relevant to biology, such as protein-DNA complex formation for antibiotic resistance, protein nanotube structure and morphology, RNA structure of the tomato bushy stunt virus, and aptamer self-assembly for sensing applications.

Nanostructured materials and devices; Nanoscale carbons; Magnetism and magnetic materials; Magnetic recording; Heat transport; Pump-probe techniques.

My research is devoted to heat and electron transport in nanoscale devices, interfaces, materials, and composites, with the aim of improving dissipation and energy efficiency of electronic devices. I am also interested in spectroscopy and optical pump-probe techniques for the characterization of materials and magnetization dynamics near phase transitions. I have experience studying the electronic properties of amorphous semiconductors and novel nanostructured materials such as carbon nanotubes, semiconducting nanowires, and graphene. I have also worked on nanoscale magnetic field sensing devices and energy-assisted magnetic recording technologies.

Nanotechnology; Nano-materials; Thin Films; Solar cells.

My research focuses on the development of space-based instrumentation, data analysis techniques and tools, and space test processes to advance planetary research and to improve the performance and reliability of space systems. For example, I am a member of the York University Argus team that is currently operating a pollution monitoring spectrometer in low Earth orbit on the CanX-2 spacecraft. This technology was awarded the Canadian Astronautics and Space Institute Alouette award in 2010. Also, I am the inventor of a novel construction technology for a space elevator which has attracted world-wide interest. In collaboration with Thoth Technology, Inc., I am currently developing a mission to Mars called Northern Light which will explore new regions of the planet. In the process, I have revived Algonquin Park Radio Observatory, and am presently using it for endeavours ranging from spacecraft tracking to very-long-baseline interferometry of pulsars.