aspuru-list April 2012

aspuru-list@lists.fas.harvard.edu

27 participants
60 discussions

[Aspuru-Guzik group list] My minestrone soup!

by abs.ccb＠gmail.com

Dear Group, sorry for the spam but I just left office and forgot I microwave a thing of minestrone soup. Its probably still in there. If someone is walking by the kitchen, can you do me a solid and shove my soup in the fridge? I'd really appreciate it. Now I'm going to eat as I'm starving! :'( Sent from my Verizon Wireless BlackBerry

12 years

[Aspuru-Guzik group list] chocolate by the printer

by Stéphanie Valleau

Leftover chocolate from my section is next to the printer! Enjoy :) Best, Stephanie

12 years

[Aspuru-Guzik group list] REMINDER: Theochem by Paul Brumer today

by Joel Yuen

Strongly encouraged for young graduate students! When: TODAY from 4 to 6 PM Where: MIT Building 4, Room 231 What: Paul Brumer http://www.chem.utoronto.ca/ppl/faculty_profile.php?id=7 is lecturing on: Quantum Coherence and Incoherence in Molecular Dynamics and Control Paul Brumer Chemical Physics Theory Group Department of Chemistry University of Toronto An essential feature of quantum mechanics is interference resulting from multiple pathways to the same final state. Loss of this coherence (i.e. decoherence) can lead to classical-like behavior. I will review the nature of this interference, the origins of decoherence, and the role of perturbations, such as lasers, in creating quantum coherence in molecules. Examples of the role of coherence in controlling molecular processes (such as internal conversion and chemical reactions) will be described. The role (?) of quantum coherence in natural biological processes will be discussed, both in models of retinal isomerization and light harvesting systems. Time permitting I will introduce a general scheme for assessing when a given external perturbation creates quantum interference in a molecular system upon which it acts. -- Joel Yuen-Zhou PhD candidate in Chemical Physics Harvard University CCB, 12 Oxford St. Mailbox 107, Cambridge, MA, USA.

12 years

[Aspuru-Guzik group list] Christoph Kreisbeck Visit: Meet / Lunch / Dinner

by Stéphanie Valleau

Dear group, *Christoph Kreisbeck* from the T. Kramer group in germany http://www.quantumdynamics.de/group.html will be visiting this coming Thursday and Friday April 19-20th as a potential postdoctoral candidate. He has worked on the photosynthetic complex frenzy: in particular on speeding up of hierarchical equation of motion with GPU's. Also, he has worked on some more *à la Heller* topics such as Quantum Hall effect etc. There will be the following opportunities to meet with him *1)* Schedule a *meeting*. Please let me know your availability to meet with him. The other option is I will come disturb you at your desks so that you introduce yourselves :) *2) Lunch* on Thursday* April 19th* *3)* *Dinner* on Thursday *April 19th* *4) Lunch* on Friday *April 20th* Obviously we have limited availability for the free food events so sign up quick :). All these are great occasions to meet an eventual future colleague and make him feel welcome! Or you can also see it as an opportunity to grill him with questions :) Best, Stephanie -- Stéphanie Valleau PhD student in Chemical Physics Harvard University CCB, 12 Oxford St. Mailbox 312, Cambridge, MA, USA

12 years

[Aspuru-Guzik group list] Reminder today: Special Harvard Electrical Engineering 4/16/12

by Joan Hamilton

> Description: Description: hseas-logo*Special****Harvard EE Seminar*** > 11-12 noon Monday, April 16, 2012 > Pierce Hall, 100F > ** > *Silicon Monolithic MEMS + Photonic Systems* > *Sunil Bhave* > Cornell University > ** > > Optomechanical systems offer one of the most sensitive methods for > detecting mechanical motion using shifts in the optical resonance > frequency of the optomechanical resonator. Presently, these systems > are used for measuring mechanical thermal noise displacement or > mechanical motion actuated by optical forces. Meanwhile, electrostatic > capacitive actuation and detection is the main transduction scheme > used in RF MEMS resonators. The use of electrostatics is convenient as > it allows direct integration with electronics used for processing the > RF signals. > > In this talk, I will introduce a method for actuating an > optomechanical resonator using electrostatic forces and sensing of > mechanical motion by using the optical intensity modulation at the > output of an optomechanical resonator, integrated into a monolithic > system fabricated on a silicon-on-insulator (SOI) platform. I will > discuss new applications enabled by this hybrid system including > Opto-Acoustic Oscillators (OAO) and Opto-Mechanical Gyroscopes (OMG). > > Biography: Sunil received the B.S. and Ph.D. degrees from Berkeley in > EECS in 1998 and 2004 respectively. In October 2004, he joined the > faculty of Cornell, where he is presently an Associate Professor in > Electrical Engineering. Sunil received the NSF CAREER Award in 2007 > and the DARPA Young Faculty Award in 2008. His students have received > the Best Student Paper Award at Ultrasonics 2009 and the Roger A. > Haken Best Student Paper Award at IEDM 2007. Sunil is the co-founder > of Silicon Clocks, which was acquired by Silicon Labs in April 2010. > He is currently on industry leave working with the MEMS Product > Development team at Analog Devices in Boston. > Host: MarkoLončar > >

12 years

[Aspuru-Guzik group list] Prof. Paul Brumer's visit this week. Sign-up for lunch and dinner slots

by Joel Yuen

Hi all, Prof. Paul Brumer http://www.chem.utoronto.ca/ppl/faculty_profile.php?id=7 is visiting Boston for Theochem. I strongly recommend his talk, he's quite funny. There are some slots available for meeting, lunch, and dinner with him. Please let me know ASAP if you are interested in attending any of the following: A) Kosher dinner (Wednesday 18, after Theochem) will occur at Rubin's http://rubinsboston.com/ which we will reach by cab from Theochem at MIT. B) Scientific discussion (Thursday 19, 11:15 AM to 12 PM), probably at the Division Room (TBA). C) Kosher lunch (Thursday 19, 12 - 1:30 PM), probably at the Division Room (TBA). Food catered from Milk Street Cafe http://www.milkstreetcafe.com/ More importantly, here's the abstract of his talk, Quantum Coherence And Incoherence In Molecular Dynamics And Control4/18/12 4:00PM MIT Building 4, Room 231Paul BrumerUniversity of Toronto<http://www.chem.utoronto.ca/ppl/faculty_profile.php?id=7> [image: Paul Brumer] An essential feature of quantum mechanics is interference resulting from multiple pathways to the same final state. Loss of this coherence (i.e. decoherence) can lead to classical-like behavior. I will review the nature of this interference, the origins of decoherence, and the role of perturbations, such as lasers, in creating quantum coherence in molecules. Examples of the role of coherence in controlling molecular processes (such as internal conversion and chemical reactions) will be described. The role (?) of quantum coherence in natural biological processes will be discussed, both in models of retinal isomerization and light harvesting systems. Time permitting I will introduce a general scheme for assessing when a given external perturbation creates quantum interference in a molecular system upon which it acts. -- Joel Yuen-Zhou PhD candidate in Chemical Physics Harvard University CCB, 12 Oxford St. Mailbox 107, Cambridge, MA, USA.

12 years

[Aspuru-Guzik group list] [Aspuru-meetings-list] Thesis defense by Roberto tomorrow

by Joel Yuen

When: Tomorrow Monday Apr 16 from 12 to 1 PM Where: Cabot Division Room at Mallinckrodt What: Roberto is defending his thesis: "Quantum Chemistry in Nanoscale Environments: Insights on Surface-Enhanced Raman Scattering and Organic Photovoltaics Abstract The understanding of molecular effects in nanoscale environments is becoming increasingly relevant for various emerging fields. These include spectroscopy for molecular identification as well as in finding molecules for energy harvesting. Theoretical quantum chemistry has been increasingly useful to address these phenomena to yield an understanding of these effects. In the first part of this dissertation, we study the chemical effect of surface-enhanced Raman scattering (SERS). We use quantum chemistry simulations to study the metalmolecule interactions present in these systems. We find that the excitations that provide a chemical enhancement contain a mixed contribution from the metal and the molecule. Moreover, using atomistic studies we propose an additional source of enhancement, where a transition metal dopant surface could provide an additional enhancement. We also develop methods to study the electrostatic effects of molecules in metallic environments. We study the importance of image-charge effects, as well as field-bias to molecules interacting with perfect conductors. The atomistic modeling and the electrostatic approximation enable us to study the effects of the metal interacting with the molecule in a complementary fashion, which provides a better understanding of the complex effects present in SERS. In the second part of this dissertation, we present the Harvard Clean Energy Project, a high-throughput approach for a large-scale computational screening and design of organic photovoltaic materials. We create molecular libraries to search for candidates structures and use quantum chemistry, machine learning and cheminformatics methods to characterize these systems and find structure-property relations. The scale of this study requires an equally large computational resource. We rely on distributed volunteer computing to obtain these properties. In the third part of this dissertation we present our work related to the acceleration of electronic structure methods using graphics processing units. This hardware represents a change of paradigm with respect to the typical CPU device architectures. We accelerate the resolution-of-the-identity Møller-Plesset second-order perturbation theory algorithm using graphics cards. We also provide detailed tools to address memory and single-precision issues that these cards often present." -- Joel Yuen-Zhou PhD candidate in Chemical Physics Harvard University CCB, 12 Oxford St. Mailbox 107, Cambridge, MA, USA. _______________________________________________ Aspuru-meetings-list mailing list Aspuru-meetings-list(a)lists.fas.harvard.edu https://lists.fas.harvard.edu/mailman/listinfo/aspuru-meetings-list

12 years

[Aspuru-Guzik group list] Cecam conference: Energy from the Sun

by Xavier Andrade

Hi, Today I learned from this conference in Sardinia: CECAM Conference Energy from the Sun Computational Chemists and Physicists Take Up the Challenge 10-14 September 2012 - Chia Laguna - Cagliari - ITALY http://www.cecam.org/workshop-820.html Perhaps someone from the group would be interested in going. The abstract deadline was today, but they moved it to April 25. Xavier

12 years

[Aspuru-Guzik group list] [Aspuru-meetings-list] Thesis defense by Alejandro today

by Joel Yuen

When: Today Friday April 13 from 2:30 to 3:30 PM Where: Cabot Division Room at Mallinckrodt What: Alejandro is defending: "Designing and Probing Open Quantum Systems: Quantum Annealing, Excitonic Energy Transfer, and Nonlinear Fluorescence Spectroscopy Abstract The 20th century saw the first revolution of quantum mechanics, setting the rules for our understanding of light, matter, and their interaction. The 21st century is focused on using these quantum mechanical laws to develop technologies which allows us to solve challenging practical problems. One of the directions is the use quantum devices which promise to surpass the best computers and best known classical algorithms for solving certain tasks. Crucial to the design of realistic devices and technologies is to account for the open nature of quantum systems and to cope with their interactions with the environment. In the first part of this dissertation, we show how to tackle classical optimization problems of interest in the physical sciences within one of these quantum computing paradigms, known as quantum annealing (QA). We present the largest implementation of QA on a biophysical problem (six di↵erent experiments with up to 81 superconducting quantum bits). Although the cases presented here can be solved on a classical computer, we present the first implementation of lattice protein folding on a quantum device under the Miyazawa-Jernigan model. This is the first step towards studying optimization problems in biophysics and statistical mechanics using quantum devices. In the second part of this dissertation, we focus on the problem of excitonic energy transfer. We provide an intuitive platform for engineering exciton transfer dynamics and we show that careful consideration of the properties of the environment leads to opportunities to engineer the transfer of an exciton. Since excitons in nanostructures are proposed for use in quantum information processing and artificial photosynthetic designs, our approach paves the way for engineering a wide range of desired exciton dynamics. Finally, we develop the theory for a two-dimensional electronic spectroscopic technique based on fluorescence (2DFS) and challenge previous theoretical results claiming its equivalence to the two-dimensional photon echo (2DPE) technique which is based on polarization. Experimental realization of this technique confirms our theoretical predictions. The new technique is more sensitive than 2DPE as a tool for conformational determination of excitonically coupled chromophores and o↵ers the possibility of applying two-dimensional electronic spectroscopy to single-molecules." -- Joel Yuen-Zhou PhD candidate in Chemical Physics Harvard University CCB, 12 Oxford St. Mailbox 107, Cambridge, MA, USA. _______________________________________________ Aspuru-meetings-list mailing list Aspuru-meetings-list(a)lists.fas.harvard.edu https://lists.fas.harvard.edu/mailman/listinfo/aspuru-meetings-list

12 years

[Aspuru-Guzik group list] [qip] meeting today

by Edward Farhi

Hi Quanta Greetings from Tel Aviv. You are meeting today at 11:00. Christian is going to speak about his recent interests. Best, 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

12 years

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aspuru-list April 2012