aspuru-list November 2013

aspuru-list@lists.fas.harvard.edu

34 participants
83 discussions

[Aspuru-Guzik group list] Free black vinyl couch-bed with 3 storage drawers

by Aspuru

Dear group members, Dori and I are rearranging furniture at home and will not need this couch-bed anymore. It cost us originally 500 back in the bay area circa 2005. We used to have it in our living room when I was a postdoc. It is well preserved and has great storage drawers. It is *free* to the first group member that agrees to come to my house (Cambrigeport) and take it away before next Saturday when we have other furniture come in. It is great as a guest bed! I will send another picture of it in the next message. Again, first come, first-serve. Alan Aspuru-Guzik Associate Professor Harvard University http://aspuru.chem.harvard.edu Sent from my mobile. Please pardon any typos.

9 years, 11 months

[Aspuru-Guzik group list] John Pendry - Dec. 4, 2013 - HQOC/ITAMP Joint Quantum Sciences Seminar

by Hamilton, Joan

**HQOC/ITAMP Joint Quantum Sciences Seminar** ***Wed, Dec. 4th, 4:00 PM, Jefferson 250*** ****John Pendry, Imperial College London**** Transformation Optics Shapes Metamaterials Metamaterials offer a huge range of new electromagnetic properties: negative refraction, spatial inhomogeneity to name only two. To exploit the possibilities offered in this new world we need a new design tool. Maxwell’s equations are exact at the classical level but lack transparency; Snell’s law is elegantly visual, an aid to the imagination, but fails to account for many vital aspects of electromagnetism. Transformation optics retains an intuitive appeal, replacing the rays of Snell’s law with the field lines of Maxwell whose equations it represents exactly. Student Presentation by Kevin Vora, Mazur Group, “Metamaterials through Nanofabrication on a not-so-nano scale” Student Presentation will begin at 4:00 PM Refreshments will be served from 4:10-4:30 PM Guest Presentation will begin at 4:30 PM Joan Hamilton Faculty Assistant to Profs. Greiner and Lukin HQOC Laboratory Administrator HUCTW Local Union Representative Harvard University Department of Physics 17 Oxford Street Cambridge, MA 02138 P: (617) 496-2544 F: (617) 496-2545

10 years, 4 months

[Aspuru-Guzik group list] [Aspuru-meetings-list] special group meeting Monday: Professor Mark Lusk

by Ryan Babbush

Hi Everyone, This Monday at 2:00pm in the Division Room we will have a special group meeting. Professor Mark T. Lusk from the Colorado School of Mines will be presenting. You can find a title and abstract for his talk below. ============================================================= *Partially Coherent Exciton Transport in Silicon Quantum Dot Mesomaterials* ============================================================= Recent progress in understanding electronic wave functions in condensed matter nanostructures has led to an ability to synthesize isolated, quantum confined building blocks with a variety of tailored optical properties. No matter what optical gap is engineered and how cleverly exciton energy is redistributed, though, novel materials composed of such nanostructures need to also exhibit efficient carrier dynamics. Transport of energy and charge is now the central issue in harnessing the true power of quantum dot materials for solar and many other uses. This is a critical bottleneck in the science because charge and exciton transport tend to proceed via low mobility, incoherent hopping associated with weak electronic coupling and high reorganization energies in these nanostructures. A number of promising strategies seek to improve energy and charge transport between quantum dots by focusing on important properties such as translational symmetry, electronic overlap, matrix encapsulation, and crystalline orientation. Our approach, though, is to consider the entire assembly as a *quantum dot mesomaterial* (QDM), wherein entirely new transport physics may emerge from the complex interactions between components. For instance, the superb exciton harvesting efficiency of photosynthetic complexes is at least partly due to conditions that support an element of coherent character for exciton transport. Here proteins and pigments are exquisitely structured and combined so that they perform a number of integrated functions—e.g. proteins serve to correlate electronic excitations on neighboring pigments, supporting coherence and allowing exciton transport with a degree of wave-like character. We seek to design materials composed of quantum dots in which components may carry out integrated tasks that optimize dynamics ranging from incoherent random walks to coherent transport. An emphasis is placed on the robustness of such transport in the face of geometric uncertainties intrinsic to synthesized systems. The computational facet of our investigation, emphasized in this talk, utilizes an open dissipative system approach, wherein a cumulant expansion strategy is used to approximate the quantum Liouville equation via a hierarchy of density operators. This has been successfully employed to scrutinize partially coherent transport in protein/pigment complexes, but here we focus on silicon quantum dot mesomaterials and use excited state many-body calculations to populate the associated meta-Hamiltonian. After an overview of the mesomaterial perspective, this talk will focus on our computational assessment of the prospects for partially coherent exciton transport through these silicon quantum dot mesomaterials. -- Ryan Babbush | PhD Student in Physics (949) 331-3943 | babbush(a)fas.harvard.edu Harvard University | Aspuru-Guzik Group 12 Oxford Street | 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

10 years, 4 months

[Aspuru-Guzik group list] [qip] Fwd: Special seminar: Nike Sun, Monday at 11:00 in E18-466A

by Ramis Movassagh

---------- Forwarded message ---------- From: Henry Cohn <cohn(a)math.mit.edu> Date: Wed, Nov 27, 2013 at 11:57 AM Subject: Special seminar: Nike Sun, Monday at 11:00 in E18-466A To: allmath(a)math.mit.edu DATE: Monday, December 2, 2013 TIME: 11:00-12:00 LOCATION: E18-466A SPEAKER: Nike Sun (Stanford) TITLE: Random constraint satisfaction problems and replica symmetry breaking ABSTRACT: Satisfaction and optimization problems subject to random constraints are a well-studied area in the theory of computation. These problems also arise naturally in combinatorics, in the study of random graphs. In the sparse regime, many of these problems exhibit long-range correlations, described by statistical physicists as "replica symmetry breaking." The physics formalism yields "1RSB" predictions for the exact location of the SAT-UNSAT transition, but none have been previously proved. With Jian Ding and Allan Sly, we determine the exact SAT-UNSAT transition in two problems within this class, the random regular not-all-equal-SAT problem and the random regular graph independent set problem. By passing to a replica symmetric model for clusters of solutions, our approach validates the 1RSB formalism for these models. The proof applies methods for the replica symmetric regime developed in earlier work with Amir Dembo, Andrea Montanari, and Allan Sly. _______________________________________________ qip mailing list qip(a)mit.edu http://mailman.mit.edu/mailman/listinfo/qip

10 years, 4 months

[Aspuru-Guzik group list] coffee club at 11

by Joey Goodknight

Next installment of the coffee club will be tomorrow at 11 AM in the breakroom! -Joey

10 years, 4 months

[Aspuru-Guzik group list] Happy Thanksgiving!

by Marlon Cummings

Dear Friends: Wishing you a happy Thanksgiving! Enjoy! MC. ------------------------- Marlon G. Cummings Lab Manager, Aspuru-Guzik Group Mallinckrodt M112 Department of Chemistry and Chemical Biology Harvard University 12 Oxford Street Cambridge, MA 02138 617-496-9964 617-496-9411 (fax) http://aspuru.chem.harvard.edu/

10 years, 4 months

[Aspuru-Guzik group list] apartment next to CCB

by Johannes Hachmann

Hi everybody, In case anyone is interested in picking up our apartment (3 minutes walk from CCB on Cambridge St), please let me know. Shorter term leases (Jan-May or Jan-Aug) come with lower rent. http://boston.craigslist.org/gbs/fee/4214878370.html Best, Johannes ----------------------------------------------------------- Dr. Johannes Hachmann Research Associate Harvard University Department of Chemistry and Chemical Biology 12 Oxford St, Rm M104A Cambridge, MA 02138 ----------------------------------------------------------- Starting 01/2014: Assistant Professor University at Buffalo The State University of New York Department of Chemical and Biological Engineering Center of Excellence in Materials Informatics Furnas Hall Buffalo, NY 14260 http://www.cbe.buffalo.edu/people/full_time/j_hachmann.php -----------------------------------------------------------

10 years, 4 months

[Aspuru-Guzik group list] Special Seminar: Nov. 26, 2pm, Division Room

by Dmitry Zubarev

Dear Colleagues, We have a Special Seminar scheduled for the next Tuesday, November 26, from 2:00 pm till 3:00 pm in the Division Room. Dr. Olga Taran Iourova (Whitesides Group) will tell us about her work in the Origins of Life. This area is relatively new for the group and we are currently building up a collaborative effort to merge theory and computations from our side with Olga's experimental research. I hope to see you on Tuesday. The abstract follows Best, Dmitry The Chemical Origin of Life As chemists, we see life as network of chemical reactions. What chemicals and reaction conditions were necessary to start these reactions? How complex did the initial reaction network need to be to become “alive”? To answer these questions we study “Chemical Fossils” - small simple molecules common to all living cells, which might be remnants of prebiotic chemistry embedded in our biochemistry, just like real fossils are remains of previous life embedded in rocks. We are looking for these “Fossils”, tracing their plausible prebiotic geochemical origins, and using them to build simple reaction networks. To illustrate this approach I will talk about two ongoing projects from our lab: the potassium-sodium gradient and redox cofactors.

10 years, 4 months

[Aspuru-Guzik group list] Postdoctoral candidate visit - december 13th

by Stéphanie Valleau

Dear group, Leslie Upton (Univ of Michigan - Goodson group) will be visiting our group on Friday December 13th. Her research interests overlap with a lot of the groups. In her own words: *My research combines quantum mechanics, nonlinear optics, and laser spectroscopy in order to study how non-classical optical fields (entangled photons) interact with organic molecules that have been developed for applications in biomedical imaging, optical limiting and light harvesting devices. My long-term research goals are to remain in the area of quantum optics/quantum science and employ interdisciplinary techniques to combine theoretical and experimental methods to continue studying ways in which non-classical optical fields interact with molecules and other systems of interest. I’m interested in ultrafast spectroscopy, electronic structure and simulation, open quantum systems and TD-DFT. * There are five time-slots for meetings with Leslie in the morning: 9:30 - 10:00am 10:00 - 10:30am 10:30-11:00am 11:00 - 11:30am 11:30 - 12:00pm Please sign up to one of these time slots. I also need 2 volunteers to join us for lunch (12:00-1.30pm). Details of her talk (Also on the 13th) will be emailed further on, Best, Stephanie

10 years, 4 months

[Aspuru-Guzik group list] thank you

by Felipe Herrera

Hi everyone, Thanks you so much for choosing and signing my son's first book. It was a very nice gesture. Soon he'll be ready to start his second book: Landau & Lifshitz's volume 3. Cheers! Felipe

10 years, 4 months

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aspuru-list November 2013