Welcome! We are the research group of Jen Dionne, Assistant Professor of Materials Science and Engineering at Stanford University. We are a diverse team of materials scientists, electrical engineers, applied physicists, and chemists researching the design and development of new materials that allow light to be controlled in ways previously thought impossible. We then use these materials to directly visualize, probe, and control nanoscale systems and phenomena - particularly those relevant to energy and biology.
We aim to address questions such as: Can optical microscopy achieve a resolution comparable to electron microscopy, to study nanoscale systems in-situ and in real-time? Can sub-bandgap photons be efficiently harvested in solar cells, to improve solar energy conversion efficiencies? Can catalytic processes be probed on the single particle or molecule level, to understand and improve catalytic reactions? And, can proteins or small molecules be optically trapped and manipulated in-vivo, to directly probe molecular mechanics and interactions in cells? Though seemingly diverse, these questions all require precise control of optical interactions, as enabled by new optical materials.
Please feel free to navigate this site or contact us for more information!
What is a typical day like for a researcher in our group? Check out our videos to learn more about our science and our culture. If you like what you see and want to join our team, please send us your resume. We're always on the lookout for smart, creative people.
|Group Video, June 2015||Russian River Canoe Trip, July 2014|
|Upconversion||Nanoscale optical tomography|
May 19, 2015: Jen presents on the D-Lab's work at the IEEE SFBA Nanotechnology Council Symposium "The promise and progress of Nanophotonics"
May 11, 2015: Amr successfully defends his thesis: "Toward direct optical manipulation of nanoscale specimens with coaxial plasmonic tweezers"! Congratulations, soon-to-be Dr. Saleh! See his presentation here!
April 25, 2015: Jen gave an overview of the D-Lab's research at this year's Admit Expo for admitted freshman. Hopefully they will join the Farm this fall!
April 16, 2015: Hadiseh successfully defends her thesis: "Metafluids and Parity-Time symmetric metamaterials: New optical material phases and phenomena"! Congratulations, soon-to-be Dr. Alaeian! See her presentation here!
April 7, 2015: The D-Lab was well-represented at MRS, with presentations from Hadiseh, Brian, Yang, Alice, Guru, Shign-Shing, Michael, Andrea, Tarun, Jen, and Ashwin! Congratulation to Hadiseh for receiving a Graduate Student Award and Shing-Shing for winning a best poster award!
April 1, 2015: Congratulations to Guru on his wedding!
March 16, 2015: Jon successfully defends his thesis, "Plasmon nanoparticles in the quantum size regime"! Congratulations, soon-to-be Dr. Scholl! See his presentation here!
March 17, 2015: Jen gave an invited seminar to the Berkeley Chemistry department. Thank you Paul and Naomi for the invitation and very fun day!
March 16, 2015: Ashwin successfully defends his thesis: "Controlling light at the nanoscale for broadband metamaterials, efficient solar cells and subwavelength 3D imaging"! Congratulations, soon-to-be Dr. Atre! See his presentation here!
March 12, 2015: Jen gave an invited seminar to the UO Physics department. Thank you Miriam and Shannon for hosting a fun visit!
March 2, 2015: Jen presented an invited seminar at the APS spring meeting in San Antonio, Texas. The talk was featured on Doug Natelson's blog
February 12, 2015: Jen is awarded a Sloan Foundation Fellowship!
January 26, 2015: Jen presented at the AP/MSE colloquium series at Caltech. Thank you, Julia for hosting my visit!
January 1, 2015: Jen is featured in a Nature New Year's article, "Hopes for the Year Ahead"! Read the article here.
November 30-December 5, 2014: Tarun, Amr, and Guru presented their work at Fall MRS in Boston.
November 12-14, 2014: Ashwin presented an invited talk on his nano-optical tomography work at the OSA incubator on the Fundamental limits of optical energy, in Washington, DC.
October 25, 2014: Jen taught a course on Nanophotonics at Classes Without Quizzes during Stanford's Reunion Homecoming.
September 23-24, 2014: The D-Lab's solar team attended the LMI-EFRC kick-off meeting at Caltech, where Ashwin presented an invited talk on his nano-optical tomography work.
September 14: The D-Lab hits the waters on a lake trip and welcomes its newest member, Marcus Minh Dionne Vu.
September 2: Jon presented an invited talk at NFO, Salt Lake City, on quantum plasmonic metamaterials.
I. Nano-optical tomography:
In collaboration with Albert Polman's group, Ashwin has developed a new technique to visualize the optical properties of materials in 3D with nanometer-scale resolution. The technique, called "Cathodoluminescence tomography" could be used to precisely locate radiative recombination centers in light emitting diodes, to probe the nanoscale distribution of defect states in organic photovoltaics, and to potentially provide new label-free avenues for biological imaging. This work is featured as the May 2015 cover of Nature Nanotechnology!
II. Upconverters Under Pressure:
In a recent Nano Letters paper, Michael and Diane have improved the upconversion efficiency of near-infrared upconverters, using pressures nearing those found in the Earth's core to compress nanomaterials. Their results indicate that only 1% change in lattice parameter is necessary to improve upconverter efficiencies, suggesting chemical synthetic approaches to the ideal lattice structure.
III. Investigating single-particle intercalation-driven phase transitions:
Andrea, Tarun, and Ai Leen have revealed the thermodynamics of PdH phase transitions in single nanocrystals, using in-situ transmission electron microscopy and electron energy loss spectroscopy. Their results reveal that individual particles are characterized by sharp isotherms, and that surface energy effects dictate the loading pressure. Their results are published in the latest issue of Nature Materials, and could impact design of next-generation energy storage materials.