aspuru-list November 2012

aspuru-list@lists.fas.harvard.edu

28 participants
58 discussions

[Aspuru-Guzik group list] Dropbox for backup.

by Alan Aspuru-Guzik

Dear group members, As you all know, we have a very nice shared Dropbox for Teams handled by Adrian. If you want 8 GB more in addition to the 200 GB that we got for the team, go here and sign in. Took me 20 secs. https://www.dropbox.com/spacerace Alan

11 years, 5 months

[Aspuru-Guzik group list] FW: Event announcement for Prof. Dresselhaus seminar

by Catherine M Bourgeois

Please forward to your groups ============== Career Paths in Academia: a Seminar and Discussion with Prof. Mildred Dresselhaus Date: Tuesday, November 13 Time: 1-2pm Room: 4-163 Contact: GSC Academics, Research, Careers, gsc-arc(a)mit.edu<mailto:gsc-arc@mit.edu> Registration preferred: RSVP form<https://docs.google.com/spreadsheet/viewform?formkey=dE5CdVZKWHozdkxKZWZTT0…> In this seminar, Prof. Dresselhaus will explore questions related to career paths in academia, such as: What are career paths in academia like? How have they changed from past to present? What future trends can we identify? Prof. Dresselhaus will also share experiences from her own career and answer questions from the audience. About the speaker: Professor Mildred Dresselhaus is a native of the Bronx, and attended New York City public schools through junior high school, and Hunter College High School. She began her independent career in 1960 as a member of the research staff at the MIT Lincoln Laboratory after her PhD at the University of Chicago (1958) and a two-year postdoc at Cornell University. During that time she switched from research on superconductivity to magneto-optics, and carried out a series of experiments which led to a fundamental understanding of the electronic structure of semi-metals, especially graphite. This led to her appointment as an MIT faculty member and eventually to appointment as an Institute Professor in the departments of Physics and Electrical Engineering. She served as the Director of the Office of Science at the US Department of Energy in 2000-01, and has been an officer in many national organizations in physics, engineering, and related areas. Honors and awards include 28 honorary doctorates worldwide. Other honors include the National Medal of Science, the Nicholson Medal for Humanitarian Service, the Compton Award, the Fermi Prize, and the Kavli Prize. Professor Dresselhaus's research over the years has covered a wide range of topics in condensed matter and materials physics. She is best known for her work on carbon science and carbon nanostructures, as well as nanoscience and nanotechnology more generally. She is also one of the researchers responsible for the resurgence of the thermoelectrics research field through her early work on low-dimensional thermoelectricity in the early 1990s. She co-chaired a Department of Energy study on "Basic Research Needs for the Hydrogen Economy" in 2003 and more recently co-chaired the National Academy Decadal Study of Condensed Matter and Materials Physics. She has co-authored more than 1400 publications including books, book chapters, invited review articles, and peer-reviewed journal articles. She is co-inventor on five US patents. Dr. Dresselhaus remains involved in activities that promote the increased participation of women in science and engineering. She is an enthusiastic chamber music player where she plays violin and viola, and enjoys spending time with her husband, four children, and five grandchildren.

11 years, 5 months

[Aspuru-Guzik group list] [IACS-events] IACS Seminar Friday, November 2: Margot Gerritsen (Stanford University) on A Computational Engineer Combusts

by Baker, Natasha

Date: Friday, November 2, 2012 Speaker: Margot Gerritsen, Associate Professor of Energy Resources and Engineering & Director of the Institute for Computational and Mathematical Engineering, Stanford University Location: Maxwell-Dworkin G125, 33 Oxford Street, Cambridge, MA 02138 Time: Informal lunch with speaker, 12:30pm. Talk, 1:00pm. Title: A Computational Engineer Combusts Abstract: Large-scale production of very heavy oil is gaining momentum. Unfortunately, production of such reservoirs typically leads to large environmental impacts. One promising technique that may mitigate these impacts is in-situ combustion (ISC). In this process, (enriched) air is injected into the reservoir. After ignition a combustion front develops in situ that burns a small percentage of the oil in place and slowly moves through the reservoir producing steam along the way. The steam moves ahead of the front, heats up the oil, makes it runnier and hence easier to produce. A side benefit of this process is that the heat thus generated often cracks the oil into heavy, undesirable components that stay behind in the reservoir and lighter, more valuable components that can be brought up to the surface. In the last few years, my colleagues and I plunged into heavy oil recovery to see if computational mathematics could make a difference in pushing this process over less environmentally friendly processes in the industry. ISC processes are notoriously hard to predict. We developed a workflow involving laboratory experiments, various simulation tools and upscaling methods that increases the confidence of the oil reservoir engineer in ISC. We hope that this will lead to a wider acceptance and use of this technique. Bio: Margot Gerritsen is a professor in the Department of Energy Resources Engineering at Stanford and director of the Institute for Computational and Mathematical Engineering (icme.stanford.edu<http://icme.stanford.edu/>). Her work is about understanding and simulating complicated fluid flow problems. Gerritsen's research focuses on the design of highly accurate and efficient parallel computational methods to predict the performance of enhanced oil recovery methods, with particular attention to gas injection and in-situ combustion processes. These recovery methods are extremely challenging to simulate because of the very strong nonlinearities in the governing equations. Outside petroleum engineering, she is active in coastal ocean simulation with colleagues from the Department of Civil and Environmental Engineering, yacht research and pterosaur flight mechanics with colleagues from the Department of Mechanical and Aeronautical Engineering, and the design of search algorithms in collaboration with the Library of Congress and colleagues from the Institute of Computational and Mathematical Engineering. For information about the future events at IACS, see http://iacs.seas.harvard.edu/events. _______________________________________________ Iacs-events mailing list Iacs-events(a)seas.harvard.edu https://lists.seas.harvard.edu/mailman/listinfo/iacs-events

11 years, 5 months

[Aspuru-Guzik group list] HQOC/ITAMP Joint Quantum Sciences Seminar - Alan Aspuru-Guzik - November 14, 2012

by Joan Hamilton

HQOC/ITAMP Joint Quantum Sciences Seminar Wednesday, November 14 * 4:00 PM * Jefferson 250 Guest Presenter: Alan Aspuru-Guzik, Harvard University "Molecules as Quantum Processors: Ultrafast quantum process tomography to study exciton transport in molecule systems" Ultrafast experiments carried out on several photosynthetic complexes from many groups around the world have shown long-lived (~100 fs - 1 ps) quantum oscillations in two-dimensional optical spectra. Evidence suggests that these are electronic in nature, but they could be vibrational in character. Our group introduced and adapted a powerful tool from quantum optics and quantum information, quantum process tomography, for its use in condensed-phase molecular experiments. We also have recently proposed an ultrafast pump-probe scheme to distinguish between vibrational and electronic coherences as a/ witness/ for electronic coherence. In this colloquium-level talk, I will describe QPT and its application to ultrafast molecular experiments. I will describe the first experimental application of the technique, which is an ongoing collaboration with Keith Nelson (MIT) on a double-walled self-assembled molecular aggregate. Our QPT results show evidence of coherent exciton transport between two J-aggregates at room temperature. Finally, I will conclude with our simulations of a natural molecular self-assembled aggregate: the Chlorosome antenna complex of green-sulfur bacteria. These simulations provide insight into the inner workings of the light harvesting apparatus of this remarkable organism that can survive in very low-light conditions. *Student presentation by: Arghavan Safavi-Maini "Quantum Phases of Dipolar Bosons in Bilayer Geometry" * * * *Refreshments will be served. * -- Joan Hamilton Faculty Assistant to Profs. Lukin and Greiner HQOC Administrative Coordinator Harvard University Department of Physics 17 Oxford Street Cambridge, Ma 02138 Phone 617-496-2544 HUCTW Local Representative for the Department of Physics

11 years, 5 months

[Aspuru-Guzik group list] [qip] Friday

by Edward Farhi

Hi Quanta We will meet on Friday November 9 at 11:00 as usual. Mario Szegedy will join us and he will also give the seminar at 2:00. See you tomorrow. Eddie ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: Edward Farhi Cecil and Ida Green Professor of Physics Director Center for Theoretical Physics Massachusetts Institute of Technology 6-300 Cambridge MA 02139 617 253 4871 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: _______________________________________________ qip mailing list qip(a)mit.edu http://mailman.mit.edu/mailman/listinfo/qip

11 years, 5 months

[Aspuru-Guzik group list] [qip] QIS seminar - Mario Szegedy - THIS Friday, 2pm, 6c-442 - Highly recommended

by Scott Aaronson

2:00 pm Friday, November 9, 2012 Massachusetts Institute of Technology Center for Theoretical Physics Quantum Information Theory Seminar Cosman Seminar Room 6c-442 "Symmetric Garden Hose Constructions" Mario Szegedy Rutgers University Group invariant garden hose constructions The Garden Hose complexity is a new communication complexity introduced by H. Buhrman, S. Fehr, C. Schaffner and F. Speelman to analyze position-based cryptography protocols in the quantum setting. We focus on the garden hose complexity of the equality function, and improve on the bounds of Buhrman at all. With the help of of a new approach and of our handmade simulated annealing based solver, we have out-performed the commercial set solvers used by Buhrman at all. We have also found beautiful symmetries of the solutions that have lead us to develop the notion of "garden hose permutation groups." Then, exploiting this new concept, we get even farther, although several interesting open problems remain. In our talk we explain the background, our algorithmic efforts, and give a pictorial presentation of the symmetries. Joint with Well Chiu, Chengu Wang and Yixin Xu. _______________________________________________ qip mailing list qip(a)mit.edu http://mailman.mit.edu/mailman/listinfo/qip

11 years, 5 months

[Aspuru-Guzik group list] how's Dropbox Teams working?

by Adrian Jinich

Hi All, This is just your friendly dropbox teams administrator (Adrian) making sure that things are working nicely, and that *you are backing up your data!!* Please let me know if e.g. you have not received the invitation to join the account, or have any questions regarding dropbox teams. best, adrian

11 years, 5 months

[Aspuru-Guzik group list] Special Seminar: IEEE Magnetics Society Distinguished Lecturer

by Catherine M Bourgeois

Please join us this Friday, November 9, for the special seminar listed below. If interested in meeting individually with the speaker, please contact Prof. Geoff Beach (gbeach(a)mit.edu<mailto:gbeach@mit.edu>) or Dr. Jagadeesh Moodera (moodera(a)mit.edu<mailto:moodera@mit.edu>). IEEE Magnetics Society 2012 Distinguished Lecturer Magnetoresistance and spin-transfer torque in magnetic tunnel junctions Shinji Yuasa National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan Friday, November 9, 2012 11:00am - noon, Chipman Room (6-104) Lunch and Refreshments will be available A magnetic tunnel junction (MTJ) consisting of a thin insulating layer (a tunnel barrier) sandwiched between two ferromagnetic electrodes exhibits the tunnel magnetoresistance (TMR) effect due to spin-dependent electron tunneling. Since the discovery of room-temperature TMR in the mid-1990s, MTJs with an amorphous aluminum oxide (Al-O) tunnel barrier have been studied extensively. Such MTJs exhibit a magnetoresistance (MR) ratio of several tens of percent at room temperature (RT) and have been applied to magnetoresistive random access memory (MRAM) and the read heads of hard disk drives. MTJs with MR ratios substantially higher than 100%, however, are desired for next-generation spintronic devices. In 2001, first-principle theories predicted that the MR ratios of epitaxial Fe/MgO/Fe MTJs with a crystalline MgO(001) barrier would be over 1000% due to the coherent tunneling of specific Bloch states. In 2004, MR ratios of about 200% were obtained for MgO-based MTJs [1]. MTJs with a CoFeB/MgO/CoFeB structure were developed for practical application and found to have MR ratios of above 200% and other practical properties [1,2]. This lecture focuses on the physics of magnetoresistance and spin-transfer torque in MTJs and the application of MTJs to various spintronic devices such as magnetic sensors, spin-transfer-torque MRAM (STT-RAM or spin-RAM) with perpendicular magnetization, and novel spin-torque oscillators [3]. In addition, new types of MTJs such as spin-filter junctions with a ferromagnetic tunnel barrier will be discussed. [1] S. Yuasa and D. D. Djayaprawira, J. Phys. D: Appl. Phys. 40, p.R337 (2007). [2] D. D. Djayaprawira, K. Tsunekawa, M. Nagai, H. Maehara, S. Yamagata, N. Watanabe, S. Yuasa, Y. Suzuki and K. Ando, Appl. Phys. Lett. 86, 092502 (2005). [3] PDF file of the lecture slides can be downloaded from http://unit.aist.go.jp/src/cie/ieee.html　with a password given at the lecture. Dr. Shinji Yuasa received a PhD in Physics from Keio University in 1996. After receiving his doctorate, he served as a staff scientist at the Electrotechnical Laboratory (Tsukuba, Japan) where he worked on spin-dependent transport in metallic magnetic multilayers. Since 2001, he has been a staff scientist at the National Institute of Advanced Industrial Science and Technology (AIST), working on the physics and device applications of MTJs. Since 2010, he has been a director of the Spintronics Research Center at AIST. He has published more than 100 peer reviewed papers and has given more than 80 invited talks at international conferences. For his achievement of the giant TMR effect in MgO-based MTJs, he has been awarded or co-awarded 20 prizes, including the Asahi Award in 2007. He is now serving as a program co-chair for the 2013 Joint MMM/Intermag Conference and is a member of the advisory committee for the MMM Conference and an editor of Applied Physics Express. ------------------------------------------------------------------------- Geoffrey Beach Assistant Professor Materials Science and Engineering Massachusetts Institute of Technology 77 Massachusetts Avenue, Room 6-101 Cambridge, MA 02139 Phone: (617) 258-0804 Fax: (617) 324-0053 Email: gbeach(a)mit.edu<mailto:gbeach@mit.edu>

11 years, 5 months

[Aspuru-Guzik group list] [Aspuru-meetings-list] group meeting this Friday

by Ryan Babbush

Hi Everyone, This week Dr. Jiahao Chen from the Van Voorhis group at MIT will be presenting group meeting. We will meet at the usual time (2:30pm on Friday) in the usual place (Mallinkrodt Division Room). An abstract of the talk is included below. Disorder and excitonic structure in organic semiconductors: a random matrix perspective ======================== Charge carriers in bulk heterojunction solar cells are formed at phase boundaries whose morphologies are poorly understood, and their transport may be influenced by disorder-induced effects such as dynamical localization or ergodicity breaking. This talk summarizes our initial studies of how disorder affects the electrical and optical properties of organic semiconductors. First, we apply our newly developed notions of partial freeness in random matrices[1] to study disorder-induced localization in the tight binding Anderson model. The density of states can be approximated with great accuracy without solving for the eigenvectors explicitly. In one dimension, the error is small and independent of the noise strength,[2] and also scales linearly with the number of nearest neighbors in more general lattices. Second, we studied thermal fluctuations in room temperature metal-free phthalocyanine (H2Pc) crystals as well as impurity doping with zinc phthalocyanine (ZnPc). Thermodynamically accessible microstates were sampled explicit from all-atom molecular dynamics simulations, and the structure of excitonic states were determined using a hybrid quantum mechanical/molecular mechanical (QM/MM) calculations using time-dependent density functional theory (TDDFT). The density of states is distinctly asymmetric, with distinct subpopulations in the tails. The blue-shifted tail is comprised exclusively of excitonic states that are localized in at least two dimensions, whereas the red-shifted tail has a much more diffuse, delocalized stucture. Numerical evidence suggests that the unusual electronic structure is produced by a new type of disorder-induced localization phenomenon due to a collective interaction beyond the nearest neighbor level. [1] JC and Alan Edelman, Partial freeness of random matrices. arXiv:1204.2257 [2] JC, Eric Hontz, Jeremy Moix, Matthew Welborn, Troy Van Voorhis, Alberto Suárez, Ramis Movassagh, and Alan Edelman. Error analysis of free probability approximations to the density of states of disordered systems. Phys. Rev. Lett. 109 (2012), 036403. arXiv:1202.5839 -- Ryan Babbush | PhD Student in Chemistry (949) 331-3943 | babbush(a)fas.harvard.edu Harvard University | Aspuru-Guzik Research Group 12 Oxford Street, Box 400 | Cambridge, MA 02138 _______________________________________________ Aspuru-meetings-list mailing list Aspuru-meetings-list(a)lists.fas.harvard.edu https://lists.fas.harvard.edu/mailman/listinfo/aspuru-meetings-list

11 years, 5 months

[Aspuru-Guzik group list] MRS Boston - registration deadline Nov 9

by Cynthia M. Chew

Hi Group, The MRS Fall Meeting is taking place this month at the Hynes Convention Center in Boston (Nov 25-30, http://www.mrs.org/fall2012/). If you will be attending, I need to register you by *5pm Fri Nov 6* for the early bird rate. If you do not let me know before the deadline, you are responsible for paying the difference between the early bird and regular rate. Once Alan has pre-approved your attendance, please let me know and I will process your registration. Best, Cynthia

11 years, 5 months

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aspuru-list November 2012