4020170120 Intermolecular Coulomb Electron-Capture in Quantum-Dot Pairs
Digital- & Präsenz-basierter Kurs
- classroom language
- DE
- aims
- The group of students is supposed to go through a research process under guidance of the supervising scientist.
Aim of the QTeam is to produce and accumulate research data, graphics and findings worth scientific publication.
The manifold of possible research direction within the frame of the project allows for several thematically connected articles such that each student will be able to express their chosen research question and findings in an individual draft of a scientific poster.
The students are invited to participate free-of-charge at the international scientific Freigeist conference 2017 (scheduled for 25th-27th September at the HZB) on the topic "Dynamics of Energy Transfer on the Nanoscale" and are invited to present their findings on international stage in form of posters.
- requirements
- The proposed seminar is recognised as a QTeam project of bologna.lab at the HU. A QTeam is a group of students that is undertaking current research with guidance by a scientist. The students are supposed to pose their own research question and work with a selection of methods towards the answer.
Possible Studies Subjects: Since the proposed QTeam project is an interdisciplinary topic due to its methods and its open questions, students of following subjects are warmly welcome to join the quest: Chemistry, Physics, Mathematics, Informatics und Engineering.
Although a mixture of represented study topics is explicitely wished for in order to use interdisciplinary synergies, none of the mentioned subjects is required in order to undertake the project.
Necessary prerequisites: Despite indifferent to the student's study subject, the project requires a basic physical and mathematical understanding in order to be able to work with the numerical experiment of thought.
The software package for quantum-mechanical simulation is mainly operating on Unix systems via Unix Shell commands. Deeper experience is not needed, however, a student's lack of aversion towards contact with Linux/Unix systems is assumed though. Basic knowledge of programming languages (Fortran/C) or script languages (awk/sh/bash) can be advantageous to understanding the computer's working but isn't necessary for the general theoretic treatment of the problem at hand.
Examples of possible research questions
Possible core topics:
The individual student's expertise and preexistant knowledge results in various individually differentiated research questions to think of. Directions in which the students could move, require good understanding in one of the following ideas.
Mathematical-theoretical: Langrangian and Hamiltonian Mechanics, Symmetry, Quantum Mechanics, Quantum Chemistry, Linear Algebra and Eigenvalue Problems, Functional Theory, Variational Calculus (Analysis), Differential Equations (second order), Differential Geometry, Multi-dimensional Calculus (Analysis), Fourier Analysis / Hilbert Analysis, Coordinate Transformations, multi-dimensional Visualisation;
Physical-experimental: Scattering Theory (Streuprozesse), semiconductor respectively solid-state physics, nanotechnology, modern materials and material development, sensor and semiconductor technologies;
Information-technological: Database Management & SQL, Data Analysis and Data Ressource Management, Scientific Computing and Project Architecture.
It is to be emphasized explicitly that a participating student needs NOT to be proficient in each of the mentioned topics but their brought knowledge will set boundaries on the depth of research questions the student will be able to tackle. (So does the limited amount of time, however.)
According aforementioned reasoning, Bachelor students are as welcome as Master students.
- structure / topics / contents
- The process of interatomic Coulomb electron capture (ICEC) was predicted as result of scattering-theoretic observations by Gokhberg and Cederbaum in 2009 - on the one hand for halogen elements in respective interaction
(Br + Cl− and Cl + Br− ), on the other hand for alkali metals and rare earth elements in the vicinity of water molecules (Mg 2+ + H2O).
In addition, ICEC has eventually been recognized as universal process in model potentials describing pairs of quantum dots due to the work by Pont, Bande and Cederbaum.
The scientific observations for this were undertaken using numerically exact electron-dynamic following the concept of the Multi-Configurational Time-Dependent Hartree (MCTDH) algorithm.
This research project is associated with the Freigeist research group for Theoretical Chemistry lead by Dr. Annika Bande in the Institute for Methods of Material Development of Prof. Dr. Emad F. Aziz of Helmholtz-Zentrum Berlin für Materialien und Energie GmbH. It investigates ICEC via electron dynamics calculations and is furthermore taking place in colaboration with Assistant Professor Dr. Federico M. Pont (Facultad de Matemática Astronomía y Física, Universidad Nacional de Córdoba).
After evaluation of the student group's collective know-how, the guiding scientist is going to briefly introduce the current state of research on the the topic. The students will define research questions to persue according to their own fields of interest and build appropriate subgroups. Possible research targets are going to be set, e.g. poster presentations or participation in research-entrepreneurial contests.
The subgroups will the work independently and self-responsible with guidance by the supervising scientist towards their scientific subquestions and will critically examine their progress and difficulties in weekly sessions with the other teams.
- assigned modules
-
UeWP Ch
UeWP
P27
- amount, credit points; Exam / major course assessment
- 2 SWS, 5 SP/ECTS (Arbeitsanteil im Modul für diese Lehrveranstaltung, nicht verbindlich)
As final session during lecture period, formally terminating the research process within the project, an open research seminar shall be held with attendance of the scientists of the HZB research group for Theoretical Chemistry. The students will present and discuss their research progress and findings with the scientists.
Depending on the choice of research question, the student has additionally or alternatively the opportunity to develop a front-page illustration for a scientific journal in agreement with the chosen quest, e.g. in case of expertise in the field of Visualisation.
- other
- The frame of the proposes QTeam project offers a broad spectrum of imaginable research directions and agrees thereby with considerations of Huber ((2013), §3, S. 250) with regard to requirements of research projects for heterogenous student groups. Diversity in depth of roles and tasks as well as differences in research contents according to skills of the team members have been taken into consideration.
Since participating students pose their own research questions within the project's focus,
three exemplary directions of research shall be outlined in the following which are determined by the student's individual expertise and interests.
Physics student towards B.Sc. with minor preexistant knowledge: yet uninvestigated parameter dependencies could be examined employing the MCTDH simulations package in order to come to concludions towards their consequences on the overall problem at hand. One could develop working hypotheses from the describing basic equations of the system which can be verified by choice of appropriate simulations. In this way, empirical rules can be found which govern the individual combinations of parameter variations. Those can thus be generalized.
Mathematics student bringing good understanding in linear algebra: as simulations alone produce onyl data sets for predetermined parameter values, it is not possible to reach general statements on this route. Alternatively, the student could follow mathematically rigorous trains of thought and apply different decomposition algorithms and completeness proofs on the general problem without the necessity to solve the computerexperiment analytically. The gained conclusions can then be verified exemplarily on the data set of the simulations by the student themselves or the team.
Student of Engineering, or with interest on applications: up-to-date, ICEC is a theoretically prognosed process in agreement with scattering theory and quantum mechanics but is yet lacking experimental proof or technological application. The student can occupy themselves with the question, how a real-world experiment would need to be set up. Which implications do the assumptions underlying the computer experiment have on the real world? How would the simulated structures have to look like and which methods are available and necessary in order to produce them? Which materials present themselves as potential candidate? Which possibilities are imaginable to use the process in a real device?
Further examples of research directions:
· constants of motion and advantageous coordinate transformations
· optimization of project architecture, compatibility with and use of SQL in Scientific Computing, data evaluation / data ressource management
· visualization of the multidimensional parameter surface for a geometric approach towards the practical problem at hand
- contact
- Axel Molle mailto:axel.molle@helmholtz-berlin.de
- literature
-
F. M. Pont, A. Bande und L. S. Cederbaum. „Electron-correlation driven capture and release in double quantum dots. J. Phys., Condens. Matter 28, 075301 (2016)
F. M. Pont, A. Bande und L. S. Cederbaum. „Controlled energy-selected electron capture and release in double quantum dots“, Version (R). Phys. Rev. B 88, 241304 (2013)
A. Bande, K. Gokhberg und L. S. Cederbaum. „Dynamics of interatomic coulombic decay in quantum dots“. J. Chem. Phys. 135, 144112 (2011)
K. Gokhberg und L. S. Cederbaum. „Interatomic coulombic electron capture“. Phys. Rev. A 82, 052507 (2010)
1 K. Gokhberg und L. S. Cederbaum. „Environment assisted electron capture“. J. Phys. B, Atomic, Molecular and Optical Physics 42, 231001 (2009)
H.-D. Meyer, U. Manthe und L. S. Cederbaum. „The multi-configurational time-dependent hartree ap- proach“. Chem. Phys. Letters 165, 73 (1990)
. .
- quod vide:
- http://www.helmholtz-berlin.de/forschung/oe/em/materialentwicklung/research/research-projects/energy-transfer/index_en.html