Want to connect to University of Alberta Wireless?

Wondering why the UWS website tells you how to connect an iPhone but not a Blackberry?

OK, I can’t tell you why UWS is interested in supporting iPhones and not Blackberries but I can tell you how to connect. It’s straightforward and can be done in less than 30 seconds using your CCID and password if you know which settings to select.

1. Go to Set Up Wi-Fi Network. (Click on header with clock » Under Set Up, Services and Options)
2. If your Wi-Fi connection was off, you’ll be prompted to “Turn on Wi-Fi to perform a scan”.
3. The BlackBerry will scan to search out available Wi-Fi connections. Generally on campus there are always three and there may be more:
   • UWS (WPA2 Enterprise)
   • Eduroam (WPA2 Enterprise)
   • HowToConnectToWireless (Open)

   The one you want is UWS (just like doing this on your laptop)

4. Click on it and it will bring up a form on Wi-Fi Security where you need to input some of your info.
   • Enterprise Sub-Type: » PEAP
   • Username: » [your CCID username]
   • Password: » [your CCID password]
   • Username: » [your CCID username]
   • CA Certificate: » Thawte Premium Server CA
   • Inner Link Security: » [Auto]
   • Token: » [none selected]
   • Disable Server Certificate Validation: » [leave this unchecked]

   Click Connect

5. The Blackberry should tell you that your manual connection was successful.
6. I’m on a 9XXX series Blackberry so the default setting is to use Wi-Fi instead of 3G (and hence not have to pay the service provider for data) when Wi-Fi is accessible. If you’re on a different Blackberry this is something you might want to look into. It’s a simple change in your browser’s settings that will look something like this.
   • Settings » Options » Advanced Options » Browser » Change “Default browser configuration:” to “Hotspot Browser”
   • Or
   • Open your Browser Menu » Options » Browser Configuration » Change “Browser:” to “Wi-Fi”.

I guess all that’s clear is that the colour changes, which is indication that I at least did something right. The quantitative measurement of the optical properties however yields better indication that a bandgap exists, rather than just basing speculation on the presence of some shimmery looking stuff. A bandgap appears as a “bump” in a reflection spectrum and a “dip” in a transmission spectrum. The reflectance spectrum is shown here:

The nanostructure of the photonic crystal is created by seeding a surface with nucleation points and then depositing a structured thin film based on a 3D lattice structure which has a B-Zone that creates a complete bandgap. An example of how the seeding works is shown at left and then two images of a structured photonic crystal thin film are shown at right. (click the images to see them larger)

My paper was published in Applied Physics Letters on August 2, 2010.

Reflectivity of a photonic crystal device fabricated by glancing angle deposition may be reversibly
altered by infiltration with an absorbing dye solution. An electric field controls the dye ion motion
through the photonic crystal. Rapid reflectance changes up to 0.4 in the crystal’s optical band gap
are demonstrated. The time evolution of the dye movement process is examined and its operation
described. This work may have applications for a passive optical display. © 2010 American Institute
of Physics. doi:10.1063/1.3473827

The figures follow:

FIG. 1. (a) Bragg stack photonic crystal microstructure fabricated using GLAD. (b) Schematic representation of assembled cell, not to scale. Reflectance is measured from the top surface.

FIG. 2. (a) Reflectance ranges achieved when driving the cell with 800 mV. Negative polarity yields a reflectance minimum, whereas positive polarity drives dye out of the crystal for a reflectance maximum. (b) Maximal reflectance variation (λ = 715 nm) driven at three voltages. Same reflectance scale as left.

FIG. 3. (a) A reflectance time response of the cell at 715 nm when addressed with a driving voltage of 1000 mV. (b) The calculated characteristic time constants of the optical response. Driving voltages of 600 mV, 800 mV, and 1000 mV are shown in light, medium, and dark gray, respectively. Gray borders indicate wavelengths where rise or fall behavior resembled a clipped exponential.

If you’re interested in a copy of the .pdf of this paper and cannot download it from the internet you’re welcome to contact me and I will pass it along via email.

If you are in San Francisco, and attending the conference, and have found this page, I’d like to invite you to attend my talk on Thursday at 11:20 in room 234 (Mezzanine). My talk is entitled “Photonic Crystal Switching by the electrophoretic movement of dye ions” and is part of the session on “Novel effects and Applications in Photonic Crystal Structures” within the “Photonic and Phononic Crystal Materials and Devices IX“. Relevant information is on pages 238-240 of the Technical Program.

Now that I’ve located all this spatially, temporally, and categorically I’d probably be wise to briefly outline the paper:

ABSTRACT: Glancing angle deposition (GLAD) facilitates the fabrication of nanostructured thin films with varying density, using a motion control algorithm governing substrate movements during film growth, which engineerings the film structure. Film architectures for specific optical applications including photonic crystals are easily produced with GLAD. A challenge in the photonic crystal field has been the realization of in-situ control of optical characteristics. We have demonstrated partial control of stopband optical characteristics using an electric field in a GLAD 1D photonic crystal by the electrophoretic movement of absorbing dye ions.

Authors: Joshua D. Krabbe, Univ. of Alberta (Canada); Michael J. Brett, Univ. of Alberta (Canada) and National Institute for Nanotechnology (Canada)

With a bit more elaboration:

The basic premise of this work is that the movement of absorbing dye ions into and out of a porous photonic crystal yields a means by which the optical properties of the stopband of the photonic crystal may be modified. The device structure (shown below) is probed for reflectance optical properties from the top surface within the operating region (delimited by dashed lines). The photonic crystal is deposited on a transparent conducting oxide film and when the sandwich structure is completed with an identical counter electrode the device becomes electrically addressable. A dissociating dye (Methylene Blue) is used and when a positive voltage (top with respect to bottom) is applied the cations of the dye (absorbing species) are driven out of the photonic crystal. Reversal of the voltage attracts these cations and absorbing dye species accumulate in the photonic crystal.

Note: this image is (very!) not to scale.

As you likely have already anticipated, the presence of absorbing species within the photonic crystal has an inhibiting effect on the reflectance. Changing the dye concentration affects the probability of photon-dye interaction. The response of reflectance properties with addressing voltage, and an examination of the time response of optical properties to electrical switching of the device will be presented; along with an elaboration of the GLAD technique used to fabricate the porous photonic crystal that forms the basis of the device.

If you can’t attend, the proceedings will be published in 2-4 weeks.

I admit I crammed a lot of annotations on the tiny little video but that’s what the pause button is for I guess. Or the replay button if you’re interested. Or the back-button on your browser after you realized what this actually was a video of.

I have to say that I thought the speeches were a ton better than expected, I wondered sometimes as an undergrad how out of touch the administration was with what actually went on on campus. While I’m probably still justified in thinking that to a certain extent what everyone had to say was particularly relevant to the occasion and as a whole rather well presented.

So as Dr. Zemp would say “I’m running out of things to say so let’s look at some pictures”

]]> http://krabbe.ca/blog/2008/219/feed 0 http://krabbe.ca/blog/2008/225 http://krabbe.ca/blog/2008/225#comments Mon, 21 Apr 2008 18:52:04 +0000 admin http://krabbe.ca/blog/?p=225

Quotes from EEBE 540 Digital Image Processing, Winter Semester 2008

• Man I’m brain dead today < pause > let me show you a picture
• Can I tell you that that is true? < pause > never trust a prof!
• Some people can whip it out fairly quickly
  
  < Followed almost inevitably by the distasteful comment from the back row >
  What? their Weiner Functions?

Quotes from EE 456 Introduction to Nanoelectronics, Winter Semester 2008

• Who can tell me what we’re going to get when we take this integral?
  
  <My response:> -13.6 eV!
  
  <pause> … right
• It’s not that Physicists don’t do useful things. They just do different things.
• There is no reality behind phenomenon, merely more phenomenon
• I’m not prepared to make any statements today, geometrically I’m a bit slow.
• To implement periodic boundary conditions, boundary conditions, to implement periodic boundary conditions, the system is modified, system is modified, modified, the system is modified by adding a term of -t_o, of -t_o, -t_o to the corners, corners where they otherwise would have been zero, the corner elements would have been zero but we modified them by adding a term of -t_o. This modification makes the matrix invertible, the matrix becomes invertible and that makes the system solvable or the equations linearly independent, the system becomes solvable because the equations are now linearly independent.
• Just trust me and you’ll be alright.
• If you do what I say you’ll be fine
• Don’t freak out on me; I’m not trying to psyche you out.

Finding time to get on the bike outside has been rough. I was forced to skip out on the Triathlon club’s first ride of the year… boohoo. I decided to write the accreditation exam to practice engineering in the United States (at some point in my career way down the road). That meant 10 hours were holed up in an exam room on day. That meant the next day when everyone else was out enjoying the beautiful weather I needed to put together a presentation about my research project for the semester. So as the rays beat down and some people managed their first sunburn of the year on their pasty thighs, I was only absorbing the radiation coming out of the LCDisplay in front of my face.

Cross Country racing starts this Wednesday evening, that’s always a highlight of my September and October so I’m going to give it a try this week. It’s short so I can probably manage OK but I’m sure Pat will once again destroy me. That does mean however that it will probably be a few more days yet until I get outside on that bike.

Soft-spoken, unassuming, and a little uncomfortable in the spotlight, Michael Brett doesn’t come across as someone who’s launched countless engineering careers and a world-class research facility.

But he has done that and more. His work as a professor of Electrical and Computer Engineering at the University of Alberta is just the foundation of an energetic career that shows no sign of slowing, even after 22 years.

Brett was honoured today as the U of A celebrated its 12^th anniversary of teaching and learning excellence Sept. 21.

The celebration, held at the Northern Alberta Jubilee Auditorium and led by U of A President Indira Samarasekera, recognized the high standard reached by the university’s faculty and students. Brett was awarded the University Cup for a dynamic career of excellence in teaching and research.

“We are absolutely delighted to award professor Brett the University Cup,” said Samarasekera. “Professor Brett has had a most prolific academic career and his discoveries have made a tremendous impact upon a variety of industry sectors. He is internationally known for his work in electrical and computer engineering and is currently at the forefront of breakthrough research in nanotechnology. The U of A is extremely proud of professor Brett and we feel honoured to celebrate his numerous achievements.”

Brett’s work with thin-film engineering has been recognized around the globe in the form of numerous research titles, publications in 200 scientific journals, creative collaborations with multinational corporations, and a software system that was successfully commercialized and sold to major players such as IBM, Intel and Toshiba.

Despite a towering list of achievements, Brett uses the word ’serendipity’ when describing the start of his career at the U of A.

“I came along at the right time,” he said.

As a newly-minted professor, Brett worked tirelessly to help pioneer the Micromachining and Nanofabrication Facility, an entity that was instrumental in having the cutting-edge National Research Council’s National Institute for Nanotechnology’s constructed on campus. Today Bret is a Senior Research Officer at NINT, a facility that shines in the U of A’s research crown.

“The Nanofab is the core facility that seeded the incredibly high level of materials and nanotechnology research now ongoing at the University of Alberta,” said David Lynch, dean of the Faculty of Engineering. “Professor Brett has made enormous contributions to research, service and teaching.”

Brett’s other titles include an iCORE professorship in Nanoengineered ICT Devices, holder of the Micralyne/NSERC/iCORE Senior Industrial Chair in Thin Film Engineering and the Canada Research Chair in Nanoengineered Thin Films.

Brett’s success also translates to the classroom where, as an enthusiastic director of engineering physics, he transformed the program from a group of 10 students to one with an enrolment that has exceeded 30, with many applicants turned away in some years. Brett has helped his students realize their dreams by lending an ear to those who have come to his door seeking career advice. By helping them focus their choices with questions as simple as where they’d like to live, Brett has steered students to rewarding worldwide posts as university academics, with NASA, Intel and here at home, with research centres like the Cross Cancer Institute.

Brett believes his job doesn’t end when a degree is awarded.

“We should care about students and their careers,” he said. And students, in turn, care about Brett. His computer is filled with ‘where are they now’ photos from grateful grads, and he has received the highest possible rating on teaching evaluations from almost every student, in classes of up to 132 people.

But when asked about his secret to meaningful teaching, Brett deflects the glory onto his students, who are already top-notch, in his view.

“I just go there and deliver the goods. I have a very talented group.”

Brett’s deep respect and patience for his students plays a large part in that success, said Andy van Popta, who has spent eight years as an undergrad and graduate student in Brett’s lab.

“He always keeps the student’s best interests in mind. He makes sure they get to conferences, helps them focus thesis work, creates worthwhile lab projects and provides as much or as little leadership as a person needs.”

Brett has a gift for making each student feel special. In this case, Brett met van Popta’s parents, gave van Popta’s younger brother some work experience in the lab, even attended van Popta’s wedding.

“He knows my whole family.”

It instills self-confidence and the idea that any goal is reachable, van Popta said

“I can only imagine if the supervisor never showed interest in anyone as an individual – it would be hard to deal with.”

Looking to the future, Brett still has a dream of his own – to reward his many research funders by creating a product that is a commercial hit within Alberta. “There’s been a lot invested in my work, and I want to pay back some of that investment.”

It could be in the form of just about anything in a lab that has no boundaries.

As for being awarded the University Cup, Brett is honoured. “I like to think of the University Cup as recognition for the great students that I have been associated with.”