Technische Universität Berlin

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Recent Submissions
Achtung: Smart! – Möglichkeiten und Grenzen der Idee der ‚Smart City‘ für deutsche Kommunen

Konieczek-Woger, Magdalena ; Naeth, Alexander (2020)

Aktuell erleben Städte u. a. als Vierte Industrielle Revolution oder Digitalisierung bezeichnete Umwälzungen. Gleichzeitig stehen sie vor Herausforderungen wie dem Klimawandel, der wachsenden Globalisierung, aber auch dem demografischen Wandel. Wachstum bzw. Schrumpfung erzeugen unterschiedliche Handlungsspielräume. Die Entwicklung von Smart-City-Ansätzen findet immer unter diesen Bedingungen s...

Triebkräfte und Potenziale des Aufbegehrens in Planungsprozessen

(2020)

Wie gehen angehende Planer und Planerinnen mit Rebellion und Widerstand in der Stadtplanung um? Diese Dokumentation führt Ergebnisse aus der Hochschullehre und einer nationalen Winterschule in Kaiserslautern zusammen und zeigt an drei bemerkenswerten Beispielen auf, dass Proteste und Konflikte Planungsprozesse bremsen und verzögern können, sie bergen jedoch auch wertvolle Anstöße und Ideen für ...

Numerical and experimental investigation of the assessment of rail damper parameters with a new lab-scaled model

Jahan Tigh Kuchak, Alireza (2020)

One of the major problem in the development of railway network is track noise. Control of the noise pollution is an important environmental concern in urban areas. Rolling noise is one of the major sources of noise, and rail dampers as an extra installed-mass on the rail are a common method to reduce the rail vibration and consequently rail noise. In most cases, the experimental results from fi...

On the discretization of a bistable cantilever beam with application to energy harvesting

Noll, Max-Uwe ; Lentz, Lukas ; Wagner, Utz von (2019)

A typical setup for energy harvesting is that of a cantilever beam with piezoceramics excited by ambient base vibrations. In order to get higher energy output for a wide range of excitation frequencies, often a nonlinearity is introduced by intention in that way, that two magnets are fixed close to the free tip of the beam. Depending on strength and position of the magnets, this can either resu...

Ad-Hoc stream query processing

Karimov, Jeyhun (2020)

Many modern applications require processing large amounts of data in a real-time fashion. As a result, distributed stream processing engines (SPEs) have gained significant attention as an important new class of big data processing systems. The central design principle of these SPEs is to handle queries that potentially run forever on data streams with a query-at-a-time model, i.e., each query i...

Fully integrated 240 GHz transmitter and receiver for high data rate communication

Eissa, Mohamed Hussein (2020)

The need for higher data rate wireless communication is increasing rapidly for different kind of applications. Hence the utilization of the wide and unallocated band above 200 GHz opens a lot of opportunities to serve these applications. This work presents the design, implementation and demonstration of fully integrated transmitter and receiver circuits for wireless communication at 240 GHz car...

Simulation-based study and analysis of the wind power integration using heat pump and thermal energy storage

Heidar Esfehani, Hamidreza (2020)

Despite the fast-growing rate of the implementation of renewable energy technologies, high fluctuations of wind feed-in supply are currently seen as the main challenge facing further feeding of wind power to electricity grids and consequently increasing the renewable share of the energy market. Considering the fact that the utility network has no capability of storing excess power production, t...

Graphene Quantum Dot-Based Electrochemical Immunosensors for Biomedical Applications

Mansuriya, Bhargav D. ; Altintas, Zeynep (2019-12-23)

In the area of biomedicine, research for designing electrochemical sensors has evolved over the past decade, since it is crucial to selectively quantify biomarkers or pathogens in clinical samples for the efficacious diagnosis and/or treatment of various diseases. To fulfil the demand of rapid, specific, economic, and easy detection of such biomolecules in ultralow amounts, numerous nanomateria...

The Alanine World Model for the Development of the Amino Acid Repertoire in Protein Biosynthesis

Kubyshkin, Vladimir ; Budisa, Nediljko (2019-11-05)

A central question in the evolution of the modern translation machinery is the origin and chemical ethology of the amino acids prescribed by the genetic code. The RNA World hypothesis postulates that templated protein synthesis has emerged in the transition from RNA to the Protein World. The sequence of these events and principles behind the acquisition of amino acids to this process remain elu...

Generation of maximally entangled states and coherent control in quantum dot microlenses

Bounouar, Samir ; Haye, Christpoh de la ; Strauß, Max ; Schnauber, Peter ; Thoma, Alexander ; Gschrey, Manuel ; Schulze, Jan-Hindrik ; Strittmatter, André ; Rodt, Sven ; Reitzenstein, Stephan (2018-04-12)

The integration of entangled photon emitters in nanophotonic structures designed for the broadband enhancement of photon extraction is a major challenge for quantum information technologies. We study the potential of quantum dot (QD) microlenses as efficient emitters of maximally entangled photons. For this purpose, we perform quantum tomography measurements on InGaAs QDs integrated determinist...

Efficient single-photon source based on a deterministically fabricated single quantum dot - microstructure with backside gold mirror

Fischbach, Sarah ; Kaganskiy, Arsenty ; Tauscher, Esra Burcu Yarar ; Gericke, Fabian ; Thoma, Alexander ; Schmidt, Ronny ; Strittmatter, André ; Heindel, Tobias ; Reitzenstein, Stephan (2017-07-05)

We present an efficient broadband single-photon source which is fabricated by a flip-chip gold-bonding technique and in-situ electron beam lithography. The device comprises a single InGaAs quantum dot that is centered at the bottom of a monolithic mesa structure and located above a gold mirror for enhanced photon-extraction efficiency. We show a photon-extraction efficiency of ηext=(18±2) % int...

Resonance fluorescence of a site-controlled quantum dot realized by the buried-stressor growth technique

Strauß, Max ; Kaganskiy, Arsenty ; Voigt, Robert ; Schnauber, Peter ; Schulze, Jan-Hindrik ; Rodt, Sven ; Strittmatter, André ; Reitzenstein, Stephan (2017-03-12)

Site-controlled growth of semiconductor quantum dots (QDs) represents a major advancement to achieve scalable quantum technology platforms. One immediate benefit is the deterministic integration of quantum emitters into optical microcavities. However, site-controlled growth of QDs is usually achieved at the cost of reduced optical quality. Here, we show that the buried-stressor growth technique...

Enhanced photon-extraction efficiency from InGaAs/GaAs quantum dots in deterministic photonic structures at 1.3 μm fabricated by in-situ electron-beam lithography

Strocka, N. ; Musiał, A. ; Schneider, P.-I. ; Mrowiński, P. ; Holewa, P. ; Burger, S. ; Quandt, D. ; Strittmatter, André ; Rodt, Sven ; Reitzenstein, Stephan ; Sęk, G. (2018-08-07)

The main challenge in the development of non-classical light sources remains their brightness that limits the data transmission and processing rates as well as the realization of practical devices operating in the telecommunication range. To overcome this issue, we propose to utilize universal and flexible in-situ electron-beam lithography and hereby, we demonstrate a successful technology tran...

Micropillars with a controlled number of site-controlled quantum dots

Kaganskiy, Arsenty ; Gericke, Fabian ; Heindel, Tobias ; Porte, Xavier ; Reitzenstein, Stephan (2018-02-12)

We report on the realization of micropillars with site-controlled quantum dots (SCQDs) in the active layer. The SCQDs are grown via the buried stressor approach which allows for the positioned growth and device integration of a controllable number of QDs with high optical quality. This concept is very powerful as the number and the position of SCQDs in the cavity can be simultaneously controlle...

Quantum-optical influences in optoelectronics - an introduction

Chow, Weng W. ; Reitzenstein, Stephan (2018-10-26)

This focused review discusses the increasing importance of quantum optics in the physics and engineering of optoelectronic components. Two influences relating to cavity quantum electrodynamics are presented. One involves the development of low threshold lasers, when the channeling of spontaneous emission into the lasing mode becomes so efficient that the concept of lasing needs revisiting. The ...

Fabrication of dense diameter-tuned quantum dot micropillar arrays for applications in photonic information processing

Heuser, Tobias ; Große, Jan ; Kaganskiy, Arsenty ; Brunner, Daniel ; Reitzenstein, Stephan (2018-09-28)

We report on the realization of a dense, large-scale array of 900 quantum dot micropillar cavities with high spectral homogeneity. We target applications in photonic information processing such as optical reservoir computing which can be implemented in large arrays of optically coupled microlasers. To achieve the required spectral homogeneity for the underlying optical injection locking, we cal...

Bioprocess Development for Lantibiotic Ruminococcin-A Production in Escherichia coli and Kinetic Insights Into LanM Enzymes Catalysis

Ongey, Elvis L. ; Santolin, Lara ; Waldburger, Saskia ; Adrian, Lorenz ; Riedel, Sebastian L. ; Neubauer, Peter (2019-09-13)

Ruminococcin-A (RumA) is a peptide antibiotic with post-translational modifications including thioether cross-links formed from non-canonical amino acids, called lanthionines, synthesized by a dedicated lanthionine-generating enzyme RumM. RumA is naturally produced by Ruminococcus gnavus, which is part of the normal bacterial flora in the human gut. High activity of RumA against pathogenic Clos...

Ceria-Based Dual-Phase Membranes for High-Temperature Carbon Dioxide Separation: Effect of Iron Doping and Pore Generation with MgO Template

Gili, Albert ; Bischoff, Benjamin ; Simon, Ulla ; Schmidt, Franziska ; Kober, Delf ; Görke, Oliver ; Bekheet, Maged F. ; Gurlo, Aleksander (2019-08-26)

Dual-phase membranes for high-temperature carbon dioxide separation have emerged as promising technology to mitigate anthropogenic greenhouse gases emissions, especially as a pre- and post-combustion separation technique in coal burning power plants. To implement these membranes industrially, the carbon dioxide permeability must be improved. In this study, Ce0.8Sm0.2O2−δ (SDC) and Ce0.8Sm0.19Fe...

Case Study on Aircraft Noise Reduction by Variation of Departure Profiles during Night Flights

Mitzkat, Mathias ; Strümpfel, Christoph (2020-02-12)

Since the civil air transportation sector has been growing significantly, with an increase not only in number of flights, but also with regards to their environmental impact, emissions have been growing to the same degree. Residents in areas around airports are therefore exposed to an increasing strain of noise pollution. Past scientific research has identified large potential through the imple...

Good Governance: A Framework for Implementing Sustainable Land Management, Applied to an Agricultural Case in Northeast-Brazil

Rodorff, Verena ; Siegmund-Schultze, Marianna ; Guschal, Maike ; Hölzl, Sonja ; Köppel, Johann (2019-08-09)

Land management needs to cope with persistent environmental and societal changes. This requires functional governance systems. The purpose of this research is to develop a good governance framework for the implementation of sustainable land management. Good governance theory is extensive, although its operationalization remains difficult. We derived a set of good governance attributes from the ...