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Using seminar-based instruction to convey contemporary research to undergraduates, at Materials Research Society 2012 Fall Meeting (Boston, MA), Monday, November 26, 2012:
talk_1955.pdf
In the standard lecture-based approach to teaching, the focus is often on content and not on the development higher cognitive skills. The seminar method of teaching focuses on the development of such important skills, including independent research, reading, writing, presenting, debating and peer review. The method involves creating an environment for students where they can interact with each other on one or more themes under the guidance of an instructor. While the focus is on the development of skills, the students must master advanced content in order to participate in the course. I will... Read more about Using seminar-based instruction to convey contemporary research to undergraduates
Turning To Your Neighbor with Peer Instruction, at Turning Technologies Miami User Conference (Miami, FL), Monday, November 12, 2012:
talk_1974.pdf
Peer Instruction (PI) is a teaching method that leverages the power of cutting-edge learning technologies, such as clickers, to transform learning. The centerpiece of Peer Instruction is the ConcepTest, a short interactive question that helps uncover student misconceptions. “Turn to your neighbor” is the classic catch-phrase of PI methodology, whereby teachers encourage students to think about a question, vote on their answer, and then turn to their neighbor to engage, rather than sitting passively in a lecture. In this presentation, we examine two big, open questions frequently posed by... Read more about Turning To Your Neighbor with Peer Instruction
Serendipity and the quest for new materials, at 9th Science and Technology in Society Forum (Kyoto, Japan), Monday, October 8, 2012:
talk_2019.pdf
Throughout history, the development of new materials and serendipity have been tightly interwoven. I will illustrate the need for exploration and risk-taking with two anecdotes
Femtosecond laser texturing and doping of metals and semiconductors for solar harvesting, at SPIE Optics and Photonics (San Diego, CA), Thursday, August 16, 2012:
talk_1977.pdf
Shining intense, ultrashort laser pulses on the surface of a crystalline silicon wafer drastically changes the optical, material and electronic properties of the wafer. The resulting textured surface is highly absorbing and looks black to the eye. The properties of this 'black silicon' make it useful for a wide range of commercial devices. In particular, we have been able to fabricate highly-sensitive PIN photodetectors using this material. The sensitivity extends to wavelengths of 1600 nm making them particularly useful for applications in communications and remote sensing.
Towards increased efficiency in solar energy harvesting via intermediate states, at Gordon Research Conference on Defects in Semiconductors, University of New England (Biddeford, ME), Monday, August 13, 2012:
talk_1973.pdf
Shining intense, ultrashort laser pulses on the surface of a crystalline silicon wafer drastically changes the optical, material and electronic properties of the wafer. The process has two effects: it structures the surface and incorporate dopants into the sample to a concentration highly exceeding the equilibrium solubility limit. This femtosecond laser "hyperdoping technique" enables the fabrication of defect- and bandgap engineered semiconductors, and laser texturing further enhances the optical density through excellent light trapping. Hyperdoped silicon opens the door for novel... Read more about Towards increased efficiency in solar energy harvesting via intermediate states
Memorization or understanding: are we teaching the right thing?, at China-US Advanced Forum on Physics Education, Tsing Hua University (Beijing, China), Monday, August 6, 2012:
talk_1963.pdf
Education is more than just transfer of information, yet that is what is mostly done in large introductory courses -- instructors present material (even though this material might be readily available in printed form) and for students the main purpose of lectures is to take down as many notes as they can. Few students have the ability, motivation, and discipline to synthesize all the information delivered to them. Yet synthesis is perhaps the most important -- and most elusive -- aspect of education. I will show how shifting the focus in lectures from delivering information to synthesizing... Read more about Memorization or understanding: are we teaching the right thing?
Anatomy of a College Readiness Assignment, at CRAFT Professional Development Institute, University of Texas at Austin (Austin, TX), Monday, June 25, 2012:
talk_1957.pdf
The College Readiness Assignment Field-Test (CRAFT) project is working to disseminate standalone lessons designed by expert educators to prepare students for college-level success. In this presentation will discuss the heart of the CRAFT project: college readiness assignments (CRAs). We will dissect CRAs and demonstrate how the various parts map to state standards.
Educating the Innovators of the 21st Century, at Strengthening Teaching and Learning in STEM Fields, LASPAU Harvard University (Cambridge, MA), Friday, June 22, 2012:
talk_1954.pdf
Can we teach innovation? Innovation requires whole-brain thinking — left-brain thinking for creativity and imagination, and right-brain thinking for planning and execution. Our current approach to education in science and technology, focuses on the transfer of information, developing mostly right-brain thinking by stressing copying and reproducing existing ideas rather than generating new ones. I will show how shifting the focus in lectures from delivering information to team work and creative thinking greatly improves the learning that takes place in the classroom and promotes independent... Read more about Educating the Innovators of the 21st Century
Femtosecond Laser Nanostructuring of Semiconductors and Metals, at 13th International Symposium on Laser Precision Microfabrication (LPM), The Catholic University of America (Washington, DC), Thursday, June 14, 2012:
talk_1949.pdf
We have developed a unique technique to change the optoelectronic properties of many materials through hyperdoping and texturing [1]. By irradiating materials, such as silicon and titanium dioxide, with a train of amplified femtosecond (fs) laser pulses in the presence of a wide variety of dopant precursors, we can introduce dopants above the solubility limit while producing surface structures that have excellent anti-reflection and light-trapping properties.

Femtosecond-laser texturing originates from the formation of laser induced period surface structures (LIPSS) and consists of semi...

Read more about Femtosecond Laser Nanostructuring of Semiconductors and Metals
Femtosecond laser doping of TiO2 for photocatalysis, at Gordon Research Seminar on Renewable Energy: Solar Fuels (Barga, Italy), Saturday, May 12, 2012:
talk_1944.pdf
We present a novel method for femtosecond-laser doping of titanium dioxide (TiO2) for above bandgap absorptance by irradiating titanium metal in the presence of oxygen and dopants. With a bandgap of 3.2 eV for the anatase crystalline phase, TiO2 most strongly absorbs in the UV range (λ < 387 nm). However, doping with metals and nitrogen has been shown to create intermediate states in the bandgap. Using femtosecond laser doping techniques on titanium in a gaseous environment, we produce laser-induced periodic surface structures. Altering the gas composition and pressure does not change the... Read more about Femtosecond laser doping of TiO2 for photocatalysis

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