Assistant Professor of Chemistry
Professor Jain received his B.Tech. from the Institute of Chemical Technology in Mumbai, India in 2003 and his Ph.D. in Physical Chemistry from the Georgia Institute of Technology in 2008. During 2008, he was a postdoctoral fellow at Harvard University. From 2009-2011 he was a Miller Fellow at the University of California at Berkeley. He will be joining the University of Illinois faculty as an Assistant Professor in Fall 2011. He has affiliations in the Department of Physics and the Beckman Institute. His research interests are in molecular and nano-optics and imaging with the goal of enhancing the understanding and control of energy transport, light-matter interactions, and chemical transformations at nanometer length scales.
The theme of the research in the Jain lab hinges on the question: how can we use light to interface better with molecules and nanostructures? The goal is to use light in unique ways to: i) resolve important nanoscale or molecular processes that are not well understood, or, ii) induce novel optoelectronic or photochemical behavior in matter. We are a diverse team with interest and expertise in spectroscopy, materials science, and condensed matter physics. The tools we use include single-molecule spectroscopy, nanofabrication, high-resolution electron microscopy, and plasmonics. The systems we investigate range from artificial photosynthetic systems to nanophotonic switches. Specific research areas include:
Super-Resolution Imaging of Heterogeneous Catalysts. Catalytic processes, despite their importance in the chemical industry as well as in solar-to-fuel conversion, remain poorly understood. This is primarily because of the involvement of surfaces that are often chemically complex and heterogeneous. In most cases, the identity of the active site is still in question. Our lab is using single-molecule super-resolution imaging techniques borrowed from the the biophysics community, and high-resolution electron microscopy, to resolve individual active sites on a catalyst surface. By mapping the distribution, structural composition, and heterogeneity of active sites, we seek to enhance understanding of catalytic materials and processes. Particular focus is on catalysts for water-splitting and CO2 to methanol conversion.
Light-Matter Interactions in the Near Field. The interaction of light with matter is primarily entailed by the excitation of electronic and vibrational modes by the electromagnetic field of light. The characteristic length scale of such excitations is typically on the molecular size scale (ca. 1 Å), whereas the characteristic length scale of the electromagnetic field can be defined for a plane wave by its wavelength (ca. 5000 Å for visible light). This disparity in length scales between a molecule and the electromagnetic field limits light-matter interactions to common dipole-type processes. By employing strong optical resonances of metal nanostructures to 'squeeze' electromagnetic fields down to the nanoscale (10 Å), our lab seeks to bridge the gap between light and molecular excitations and uncover novel photochemistry and photophysical behavior in quantum dots, metalloproteins, chiral molecules, photovoltaic, and photosynthetic systems.
Imaging Phase Transitions in Single Nanocrystals. Phase transitions in solid-state materials often involve interesting dynamics. Since macroscopic solids are typically polycrystalline, such dynamics is smeared out in studies on bulk solids, due to ensemble averaging over different crystalline domains. By acquiring snapshots of a single nanocrystalline domain undergoing a phase transition, our lab is attempting to uncover the dynamic trajectory involved in the nucleation of a new phase. We are developing new optical and spectroscopic methods to acquire snapshots of model phase transitions and also using these techniques to learn new facts about fundamental phenomena such as crystal growth, impurity doping, and correlated electron systems.
Prospective postdocs, students, and collaborators interested in the above research projects are welcome to contact us.
Selected Articles in Journals
- J. B. Rivest, L.-K. Fong, P. K. Jain, M. F. Toney and A. P. Alivisatos, "Size dependence of a temperature-induced solid-solid phase transition in copper (I) sulfide, " Journal of Physical Chemistry Letters, 2, 2402 (2011).
- C. L. Choi, H. Li, A. C.K. Olson, P. K. Jain, S. Sivasankar and A. P. Alivisatos, "Spatially-indirect emission in a luminescent nanocrystal molecule," Nano Letters, 11, 2358 (2011).
- J. M. Luther*, P. K. Jain*, T. Ewers, and A. P. Alivisatos, "Localized surface plasmon resonances arising from free carriers in doped quantum dots," Nature Materials,10, 361 (2011) *equal contribution
- P. K. Jain and M. A. El-Sayed, "Plasmonic coupling in noble metal nanostructures," Chemical Physics Letters, 487, 153 (2010)
- S Sheikholeslami*, Y.-W. Jun*, P. K. Jain*, and A. P. Alivisatos, "Coupling of optical resonances in a compositionally asymmetric plasmonic nanoparticle dimer," Nano Letters, 10, 2655 (2010)
- P. K. Jain, Y. Xiao, R. Walsworth, and A. E. Cohen, "Surface plasmon resonance-enhanced magneto-optics (SuPREMO): Enhanced inter-band Faraday rotation in gold-coated iron oxide nanocrystals," Nano Letters, 9, 1644 (2009)
- P. K. Jain and M. A. El-Sayed, "Noble metal manoparticle pairs: Effect of medium for enhanced nanosensing," Nano Letters, 8, 4347 (2008)
- P. K. Jain, X. Huang, I. H. El-Sayed, and M. A. El-Sayed, "Noble metals at the nanoscale: Optical and photothermal properties and applications in imaging, sensing, biology, and medicine," Accounts of Chemical Research, 41, 1578 (2008)
- P. K. Jain and M. A. El-Sayed, "Surface plasmon resonance sensitivity of metal nanostructures: Physical basis and universal scaling in metal nanoshells," Journal of Physical Chemistry C (Letter), 111, 17451 (2007)
- P. K. Jain and M. A. El-Sayed "Universal scaling of plasmon coupling in metal nanostructures: Extension from particle pairs to nanoshells," Nano Letters, 7, 2854 (2007)
- P. K. Jain, W. Huang, and M. A. El-Sayed "On the universal scaling behavior of the distance decay of plasmon coupling in metal nanoparticle pairs: A plasmon ruler equation," Nano Letters, 7, 2080 (2007)
- P. K. Jain, S. Eustis, and M. A. El-Sayed "Plasmon coupling in gold nanorod assemblies: Optical absorption, Discrete Dipole Approximation simulation and exciton coupling model," Journal of Physical Chemistry B 110, 18243 (2006)
- P. K. Jain, W. Qian, and M. A. El-Sayed "Ultrafast cooling of photoexcited electrons in gold nanoparticle-thiolated DNA conjugates involves the dissociation of the gold-thiol bond" Journal of the American Chemical Society, 128, 2426 (2006)