UofC NanoGroup‎ > ‎

nanoTalks

We are encouraging students (undergraduate, graduate, post-docs) interested in nanotechnology to attend our regular nanoTalk presentations. Learn more about research in nanotechnology at the UofC!

Are you interested in showing off how nanotechnology is used in your project, in your research, in your field of study? The UofC nanoGroup would like to invite you to present an invited talk to your peers. Let us know at nanocalgary@gmail.com


Upcoming nanoTalks:

Diamond Optomechanics
JP Hadden (Physics & Astronomy) - December 15, 2016 from 4-5 pm
Location: Science B 142 (SB 142)

Nanoscale optomechanical devices which allow coupling between light and mechanical motion open the way to exquisite sensing capabilities, as well as the opportunity to probe these interactions down to the quantum level.  Diamond possesses excellent optical and mechanical properties and is therefore an ideal material in which to engineer high mechanical frequency optomechanical devices.  In addition it is host to colour centres such as the Nitrogen Vacancy (NV-) centre which is a leading candidate for use in solid state quantum technologies.  Strain mediated coupling between the electronic spin of the NV centre and mechanical motion will allow for optical spin manipulation, as well as novel hybrid abilities [1].

Here we present the demonstration of optomechanics in diamond nanobeam and microdisk structures.  Devices were fabricated in single crystal diamond using standard ICPRIE techniques in addition to a quasi-isotropic oxygen plasma etch, which allowed undercutting of the devices with surfaces smooth enough to support mechanical and optical resonators [2].  A dimpled taper fibre was used to probe the devices optical and mechanical resonances.  

High quality factor mechanical resonances in nanobeams with frequencies up to 2 MHz were demonstrated.  They were driven into self-oscillations with amplitude exceeding 200 nm through photothermal effects [3].  Microdisks with mechanical frequencies up to 2 GHz were also demonstrated with low dissipation which should make room temperature single phonon-photon coupling possible.  Radiation pressure and cavity back-action driven self-oscillations were observed in, driving stress fields of up to 30 MPa.  These devices showed optical resonances in both the infra-red and visible spectrums, with optical quality factors of up to 11,000 near the NV- centre’s line, approaching 100,000 at 1550 nm [4].  We will discuss the potential for interfacing these devices and NV centres. 

[1] Golter et al. (2016). PRL, 116(14), 143602.; 
[2] Khanaliloo, et al. (2015). Nano Letters, 15(8), 5131–5136.; 
[3] Khanaliloo et al. (2015). PRX, 5(4), 041051.; 
[4] Mitchell, M., et al. (2016). Optica, 3(9), 963. 



Past nanoTalks:

Metal Nanoparticle Array Formation by Pulsed Laser-induced Thin Film Dewetting and Their Applications
Yujun Shi (Chemistry) - November 30, 2016 from 4-5 pm
Location: Science B 142 (SB 142)

Ordered arrays of metal nanoparticles (NPs) have found many applications, for example, as catalyst arrays for the growth of semiconductor nanowires/carbon nanotubes and as model electrodes for electrocatalyst evaluation. Compared to wet chemical methods and lithography- based nanopatterning, pulsed laser-induced dewetting (PLiD) is a versatile, simple, and high throughput method for the synthesis of metallic NPs of controlled size and shape. In this talk, I will present our recent work on the formation of Au, Pt, and Ag NPs via PLiD of single-layer metallic thin films and the fabrication of bimetallic NPs from PLiD of bilayer thin films. The application of the Au NPs as catalysts in silicon nanowire growth in a chemical vapor deposition process will also be discussed.

Recent Progress on Multi-Modal Micro/Nanostructured Sensors for Trace Amount of Gas/Vapor Detection
Seonghwan (Sam) Kim (Mech & Manu Eng) - October 26, 2016 from 4-5 pm
Location: Science B 142 (SB 142)

Chemical sensors based on micro/nanoelectromechanical systems (M/NEMS) offer many advantages. However, obtaining chemical selectivity in M/NEMS sensors using chemoselective interfaces has been a longstanding challenge. Despite their many advantages, M/NEMS devices relying on chemoselective interfaces do not have sufficient chemical selectivity. Therefore, highly sensitive and selective detection and quantification of chemical molecules using real-time, miniature sensor platforms still remains as a crucial challenge. Incorporating photothermal/photoacoustic spectroscopic techniques with M/NEMS using quantum cascade lasers (QCLs) can provide the chemical selectivity without sacrificing the sensitivity of the miniaturized sensing system. In this talk, I will present a recent progress on the development of multi-modal nano/microstructured MEMS sensors for trace amount of gas/vapor detection.

Role of nanoparticles in heavy hydrocarbon processing: importance of nanosize and surface modifications
Nashaat Nassar (Chem & Petr Eng) - March 23, 2016 from 4-5pm
Location: Science Theatre 063 (ST 063)
 
Dr. Nassar is an assistant professor in the Department of Chemical and Petroleum Engineering at the University of Calgary. He received his Ph.D. in chemical engineering from the University of Calgary, in 2008. After graduation, he worked at the Alberta Ingenuity Centre for In-Situ Energy, becoming a Research Group Leader and Corporate Project Manager. He joined the University of Calgary in June 2014 as an assistant professor. His main research interests are in the areas of nanotechnology and its applications in oil and gas industry, such as enhanced heavy oil upgrading and recovery, inhibition of asphaltene formation damage, asphaltene gasification, oil spillage remediation, produced and wastewater treatment, as well as air pollution control and polymeric nanocomposites. He published over 70 peer-reviewed publications and made over 50 technical presentations. He co-edited one book and filed three United States patents.

CMOS imagers and entrepreneurship
Orly Yadid-Pecht (Elec & Com Eng) - March 14, 2016 from 3-4pm
Location: Science B 144 (SB 144)
Co-organized with COPSS and ECEG.

Nano-catalyst enabling an economically and environmentally competitive oil sands business
Pedro Pereira Almao (Chem & Petr Eng) - February 17, 2016 from 4-5pm
Location: Science Theatre 147 (ST 147)

Nanophotonic optomechanics and quantum optics
Paul Barclay (Physics) - January 13, 2016
Date: Wednesday January 13, 2016 from 4-5pm
Location: Science B 142 (SB 146)

By trapping light in volumes comparable an optical wavelength, nanophotonic devices enhance forces (e.g. radiation pressure) and light matter interactions (e.g. coupling rates between single photons and single atoms). In this talk I will show how researchers in my lab use these devices to create force and torque sensors that operate with record precision, optical wavelength converters with record efficiency, and optomechanical interfaces for controlling the quantum state of electron spins in diamond in new ways.



Lubricating Properties of Graphene
Philip Egberts (Mech & Manu Eng) 
Date: Wednesday December 16, 2015 from 4-5pm
Location: Science B 142 (SB 142)


Single asperity friction experiments on graphene, as well as other atomically thin films, have shown that single layers of atoms can dramatically reduce friction when compared to the substrate materials.  In particular, the low adhesion and the high tensile modulus typically measured on graphene makes it an ideal solid lubricant for a variety of applications, including nano/microelectromechanical (N/MEMS) system, magnetic storage, and other industrial applications. However, a number of factors have been shown to significantly influence the ability of graphene to reduce friction, including the number of graphene layers used, the adhesive properties of the underlying substrate, and chemical functionalization of the surface. In this study, the lubricating properties of graphene will examined, specifically exfoliated graphene on silicon wafers and chemical vapour deposition (CVD) grown graphene on both polycrystalline copper foils and single crystals of platinum. Additional factors, such as environmental exposure, surface topographical structure, and surface energies will be discussed in terms of their influence on the ability of graphene to lubricate a surface. Atomic scale mechanisms of lubrication will be discussed by combining experimental atomic force microscopy results, atomistic simulations, and analytical friction theories.


A silicon nano-photonic based FTIR spectrometer and applications in the oil and gas industry
Yonathan Dattner [Luxmux]
Date: Wednesday November 18, 2015 from 4-5pm
Location: Science Theatre 147 (ST 147)


Photochemistry at the nano scale
Belinda Heyne [UofC, Chemistry department]
Date: Wednesday October 14, 2015 from 4-5pm
Location: Science Theatre 147 (ST 147)

Dr. Belinda Heyne is an Associate Professor in the Chemistry Department at the University of Calgary. Her research interest lies in supramolecular photochemistry involving the organization of molecules into ordered aggregates due to weak interactions. In particular, Dr. Heyne’s work focuses in understanding the effects of salt on the organization of small cyanine dyes. This research topic led her group to develop new synthetic techniques to generate both organic and metallic nanoparticles. More recently, her group designed novel core-shell nanoparticles capitalizing on metal enhancement effects and allowing for the amplification of singlet oxygen production. These new nanoparticles can find application in photodynamic therapy treatment of microbial infection.


Organ on chip platforms using microfluidics and tissue engineering approaches

Amir Sanati Nehzad [UofC, department of Mechanical and Manufacturing Engineering]
Date: Wednesday September 23, 2015 from 4-5pm
Location: Science Theatre 147 (ST 147)

Amir Sanati-Nezhad received his M.Sc. degree in Mechanical Engineering from Amirkabir University of Technology in Tehran (Iran) and his Ph.D. degree from the Optical Bio-Microsystems Laboratory at Concordia University in Montreal. He did two years of postdoctoral research in the Department of Biomedical Engineering at McGill University and Harvard - MIT Health Sciences and Technology. He is currently an assistant professor at the Department of Mechanical and Manufacturing Engineering and affiliated with Biomedical Engineering program at University of Calgary. His current research interests include BioMEMS, organ on chip, bioinspired microfuidics, lab-on-a-chip, tissue engineering, single cell analysis, and biosensors.



Raman Scattering: a journey from scientific curiosity to awesome applications

Alex Brolo [University of Victoria]
May 29, 2015

Vibrational spectroscopy provides a pattern of bands that can uniquely identify (and even quantify) chemical species. The energies of vibrational transitions are in the infrared range, and, typically for chemical applications, a vibrational spectrum is obtained by IR absorption. However, vibrational information can also be obtained by Raman scattering, as demonstrated by C.V. Raman in the 1930’s. The “Raman effect” is generally very weak and for decades was treated as a scientific curiosity, only explored for scientific research and niche applications. In the last few years, advances in lasers and detection technologies have revolutionized the field of Raman scattering by generating low-cost (and even miniaturized!) Raman instruments. Moreover, developments in enhanced Raman methods, based on resonance effects, nonlinear effects, and nanotechnology, have provided avenues to boost the Raman efficiency and broadened the possible range of applications for the technique.
In this presentation, we will provide a historical perspective of the advances in Raman scattering, culminating to a range of very interesting applications. We will demonstrate how Raman spectroscopy is now a workhorse characterization method for some industries (particularly pharmaceuticals). We will also discuss advances applications of Raman scattering in cancer research and in single molecule detection.


Quantum and Thermal Polaritons (formerly: Hyperbolic Metamaterials)

Zubin Jacob [University of Alberta]
November 12, 2014

In 1987, the search for a medium that expels vacuum fluctuations in a prescribed bandwidth and rigorously forbids spontaneous emission led to the concept of the photonic crystal. Here, we argue that the search for the opposite effect: enhancing vacuum and thermal fluctuations inside a medium within a prescribed bandwidth can be accomplished by an artificial medium known as a hyperbolic metamaterial. We will present the fluctuational electrodynamics of such media with hyperbolic dispersion and show that they exhibit broadband super-planckian thermal emission in the near-field. We will also present the quantum nanophotonics of hyperbolic media where the enhanced vacuum fluctuations within the medium leads to a broadband Purcell effect. Finally, we will present associated effects such as optical topological transitions which make it viable to experimentally detect the signatures of these predicted effects.


DNA Detection- Don’t FRET about it

Biomod Team [University of Calgary]
October 17, 2014 
This talk focuses on the nano biosensor created by the UofC BioMod Team called the Stampedosaurs. They will be traveling to the BIOMOD competition hosted by Harvard University in November 2014. Teams from all over the world will be showcasing their work.



August 13, 2014: Patrick Lai


Quantum nanophotonics and nanomechanics with diamond

Marko Lončar [Harvard University]
Sponsored by: Institute for Quantum Science & Technology
Co-Sponsored by: OSA Student Chapter 

February 26, 2014


Diamond possesses remarkable physical and chemical properties, and in many ways is the ultimate engineering material - “the engineer’s best friend!” For example, it has high mechanical hardness and large Young’s modulus, and is one of the best thermal conductors. Optically, diamond is transparent from the ultra-violet to infra-red, has a high refractive index (n = 2.4), strong optical nonlinearity and a wide variety of light-emitting defects. Finally, it is biocompatible and chemically inert, suitable for operation in harsh environment. These properties make diamond a highly desirable material for many applications, including high-frequency micro- and nano-electromechanical systems, nonlinear optics, magnetic and electric field sensing, biomedicine, and oil discovery. One particularly exciting application of diamond is in the field of quantum information science and technology, which promises realization of powerful quantum computers capable of tackling problems that cannot be solved using classical approaches, as well as realization of secure communication channels. At the heart of these applications are diamond’s luminescent defects—color centers—and the nitrogen-vacancy (NV) color center in particular. This atomic system in the solid-state possesses all the essential elements for quantum technology, including storage, logic, and communication of quantum information. I will review recent advances in nanotechnology that have enabled fabrication of nanoscale optical devices and chip-scale systems in diamond that can generate, manipulate, and store optical signals at the single-photon level.

 


Modulating light at the micro- and nano-scale

Joyce Poon [University of Toronto]
Sponsored by: Institute for Quantum Science & Technology
Co-Sponsored by: OSA Student Chapter

February 19, 2013


The convergence of computing and communications is opening significant opportunities for integrated photonics. New optoelectronic devices and circuits are needed to enable future high capacity, energy efficient communications at many different levels, from trans-continental to chip-scale networks. Simultaneously, the field of integrated photonics itself is transforming rapidly due to the growing availability of sophisticated fabrication and foundry processes. Some of the most important devices in an optical communication link are optical modulators and switches, which impart data signals onto light waves. In this talk, I will present my group's research on the modulation of light at the micro- and nano-scale using silicon, hybrid silicon, and metal-dielectrics. Our work spans from near-term applications to exploratory investigations. Specifically, I will describe 1. High-speed silicon microring modulators that circumvent the modulation bandwidth limitations imposed by their intracavity optical dynamics 2. Sub-volt, broadband, compact plasmonic switches with record-high extinction ratios incorporating a phase-transition oxide material, vanadium dioxide 3. Ultra-low energy self-amplitude/phase modulation in sub-wavelength nano-apertures.