Welcome! We are the research group of Jen Dionne, Assistant Professor of Materials Science and Engineering at Stanford University. Our research investigates metamaterials, including their fundamental electrodynamic properties and applications to solar energy and bioimaging. We are especially interested in designing new materials with optical and electrical properties not accessible in nature and applying those materials to problems of global significance. Our lab specializes in visible-frequency negative index materials, active metamaterials, and colloidal-nanocrystal materials. Please feel free to navigate this site or contact us for more information!
When material dimensions approach the nanometer-scale, many unusual and exotic optical phenomena arise. In plasmonic and nanocrystalline metamaterials, these phenomena can include negative refraction, electromagnetic cloaking, and even quantum levitation. Research in our group is devoted to developing new solid-state and colloidal metamaterials and investigating their fundamental optical, electrical, and chemical properties. Ongoing projects include research into the electrodynamics of negative index materials, coupled plasmon-quantum dot systems, attractive and repulsive casimir forces, transformation optics, and single-nanoparticle nanophotonics.
Controlling light-matter interactions from classical down to quantum scales motivates applications ranging from solar energy conversion to sub-diffraction-limited microscopy. Currently, the Dionne group is focussed on three applications of plasmonic and nanocrystalline metamaterials: 1) developing efficient photovoltaic and photocatalytic systems for clean energy storage and environmental cleanup; 2) optically sensing and controlling neuronal transmission; and 3) exploring device applications of negative index materials, including sub-diffraction limited lenses and electromagnetic cloaks. All applications rely on the unique ability of plasmons and quantum dots to localize and enhance electromagnetic fields in unprecedented ways.
Latest News
April 21: Congratualtions to 2012 NSF fellowship recipients Brian, Diane, and Justin!!
April 21: Jen served as a mentor for Bay Area students at She++, the first annual conference for women in technology. Congratulations to all the amazing Stanford students who organized the event!
April 19: Jen receives the Outstanding Young Alum award from her undergraduate alma mater, Washington University in St. Louis!
April 17: Jen presented an invited talk at the SPIE conference in Brussles!
April 10: With Dr. Luke Sweatlock and Dr. Jao van de Lagemaat, Jen helped organize the "Plasmonic Materials & Metamaterials" Symposium of MRS.
April 8: Jen presented an invited talk at the Frontiers of Plasmonics conference in Chengdu, China.
March 22: Jon's paper is published as the cover article in Nature!
Article: "Quantum plasmon resonances of individual metallic nanoparticles"
News & Views: "Plasmons go Quantum"
Commentary: "Plasmons resonate in atomic-scale metal particles"
March 16: The Dionne Group holds its official Lab-Warming Party! Thanks to Alan from Princeton Instruments for generously funding the event!
January 31: Jen is awarded a CAREER award from the National Science Foundation!
January 12: Ashwin and Hadiseh each have invited articles published in the "Green Photonics" issue of the Journal of Optics: "Towards high efficiency upconversion with plasmonic nanostructures" and "Optimized light absorption in Si wire array solar cells"
January 5: Amr's paper on efficient plasmonic gain is published in Physical Review B! "Waveguides with a silver lining: Low threshold gain and giant modal gain in active cylindrical and coaxial plasmonic devices"
Featured Research
I. Quantum Plasmons:
Jon Scholl and Ai Leen Koh demonstrate that metal nanoparticles with dimensions between one and ten nanometers exhibit plasmon resonances governed by quantum mechanical effects, as probed with electron microscopy and spectroscopy. Their results appear as the cover Article in the March 22 edition of Nature.
II. Nanowire Solar Metamaterials:
Recent calculations by Hadiseh Alaeian determine the ideal nanowire dimensions and lattice configuration for optimal photovoltaic conversion. Her results were published as an invited article in the Journal of Optics on January 12.
III. Plasmonic Gain:
Recent calculations by Amr Saleh indicate the potential for gain-based plasmonic devices with low required threshold gains. Properly designed plasmonic structures can strongly enhance the gain factor of nonlinear materials, despite the higher losses usually associated with metals. His results, published in Physical Review B on January 5, will enable efficient nanoscale plasmon amplifiers, spasers, and lasers.
IV. Magnetic and Electric Fano Resonances:
Recent calculations by Sassan Sheikholeslami and Aitzol Garcia demonstrate Fano-like interference effects between electric and magnetic modes in visible-frequency "metamolecules." Their results, pulished in Nano Letters on August 5, will enable exquisite spatial and temporal control of electromagnetic hotspots, with compelling applications for molecular and biosensing.
V. Solar Upconversion Calculations:
Recent calculations by Ashwin Atre indicate the promise of upconversion for photovoltaics. Ashwin's results, which were published in the Journal of Applied Physics on August 4, show that upconversion can significantly increase solar cell efficiencies, even for realistic upconverting materials and non-concentrated sunlight.
