Geoff Hutchison is the 2018 Tina and David Bellet Excellence Awardee. The award recognizes his effectiveness and his innovations in teaching. Among many innovations Hutchinson developed Avagadro molecular editor; with that software, he designed projects hat allow Physical Chemistry students to perform quantum mechanical calculations to visualize results/concepts.
PQI Members Sergey Frolov, David Pekker, Noa Marom, Michael Hatridge, Benjamin Hunt, and Hrvoje Petek featured on Pitt Website for their accomplisment on landing $4.8M award from National Science Foundation (NSF) for International Research and Education (PIRE) program.Sergey Frolov will be the Director of new PIRE. Hrvoje Petek, Michael Hatridge and David Pekker are other PQI co-PIs for this project. The duration of the program is 5 years.
Kevin Chen and team have demonstrated that the behavior of particles of light can be made to match predictions about the four-dimensional version of the "quantum Hall effect"—a phenomenon that has been at the root of three Nobel Prizes in physics—in a two-dimensional array of "waveguides."
“For the first time, physicists have built a two-dimensional experimental system that allows them to study the physical properties of materials that were theorized to exist only in four-dimensional space"
Recently, Tevis D. B. Jacobs and colleagues have shown how silicon- and oxygen-containing hydrogenated amorphous carbon (a-C:H:Si:O) coating enhance the thermal stability in vacuum, but tremendously increases the thermo-oxidative stability and the resistance to degradation upon exposure to the harsh conditions of low Earth orbit (LEO). These findings provide a novel physically-based understanding of the superior stability of a-C:H:Si:O in harsh environments compared to a-C:H.
New research from the Giannis (Yanni) Mpourmpakis and his team introduces the first universal adsorption model that accounts for detailed nanoparticle structural characteristics, metal composition and different adsorbates, making it possible to not only predict adsorption behavior on any metal nanoparticles but screen their stability, as well. The research combines computational chemistry modeling with machine learning to fit a large number of data and accurately predict adsorption trends on nanoparticles that have not previously been seen. By connecting adsorption with the stability of nanoparticles, nanoparticles can now be optimized in terms of their synthetic accessibility and application property behavior. This improvement will significantly accelerate nanomaterials design and avoid trial and error experimentation in the lab. Their work was published in Science Advances on Sept. 13, 2019.
The ability to combine continuously tunable narrow-band terahertz (THz) generation that can access both the far-infrared and mid-infrared regimes with nanometer-scale spatial resolution is highly promising for identifying underlying light-matter interactions and realizing selective control of rotational or vibrational resonances in nanoparticles or molecules. Here, we report selective difference frequency generation with over 100 THz bandwidth via femtosecond optical pulse shaping. The THz emission is generated at nanoscale junctions at the interface of LaAlO3/SrTiO3 (LAO/STO) that is defined by conductive atomic force microscope lithography, with the potential to perform THz spectroscopy on individual nanoparticles or molecules. Numerical simulation of the time-domain signal facilitates the identification of components that contribute to the THz generation. This ultra-wide-bandwidth tunable nanoscale coherent THz source transforms the LAO/STO interface into a promising platform for integrated lab-on-chip optoelectronic devices with various functionalities.
Read more here.
American Association for Advancement of Science (AAAS) has appointed Jeremy Levy as member of its 2018 lifetime fellowship cohort. AAAS will recognize the award during its annual meeting on February 16, 2019.
Levy’s research centers around the field of oxide nanoelectronics, quantum computation, quantum transport and nanoscale optics, semiconductor and oxide spintronics, and dynamical phenomena in oxide materials and films.
Levy will join a list of distinguished scientists including inventor Thomas Edison, astronomer Maria Mitchell and computer scientist Grace Hopper.
The single-shot measurements offer a unique opportunity to study fundamental properties of non-equilibrium condensation in the presence of a reservoir. David Snoke and his colleagues have recently reported an insight into spontaneous condensation by imaging long-lifetime exciton polaritons in a high-quality inorganic microcavity in a single-shot optical excitation regime, without averaging over multiple condensate realisations. The results are published in the Journal of Nature Communications. They have demonstrated that how condensation is strongly influenced by an incoherent reservoir and that the reservoir depletion, the so-called spatial hole burning, is critical for the transition to the ground state.
The recently published paper in journal of ACS NANO on Ultrafast Microscopy of Spin-Momentum Locked Surface Plasmon Polaritons is an essential research for designing optical elements to control spin-polarized SPP (surface plasmon polaritons) fields on the nano femto scale. Hrvoje Petek and his colleagues have shown two-photon photoemission electron microscopy images formed by coupling and propagation of longitudinal and transverse components of SPP fields of light. Further, they have also shown the spin-momentum locked SPP wave packets launched with circularly polarized excitation propagate at the same phase and group velocities as for the linearly polarized excitation using time-resolved experiments.
Lillian Chong and her colleagues have recently reported, in the Journal of Nature Communications, a computational design strategy in synergistic combination with biophysical experiments to rationally improve the response time of an engineered protein-based Ca2+-sensor in which the switching process occurs via mutually exclusive folding of two alternate frames. This strategy identifies mutations that increase switching rates by as much as 32-fold, achieving response times on the order of fast physiological Ca2+ fluctuations. This computational design strategy is general and may aid in optimizing the kinetics of other protein conformational switches.