Bypassing state initialisation in perfect state transfer protocols on spin-chains

Although a complete picture of the full evolution of complex quantum systems would certainly be the most desirable goal, for particular Quantum Information Processing schemes such an analysis is not necessary. When quantum correlations between only specific elements of a many-body system are required for the performance of a protocol, a more distinguished and specialised investigation is helpful. Here, we provide a striking example with the achievement of perfect state transfer in a spin chain without state initialisation, whose realisation has been shown to be possible in virtue of the correlations set between the first and last spin of the transmission-chain.Comment: 8 pages, 2 figures, RevTeX

Dynamic Acoustic Control of Semiconductor Quantum Dot-Based Devices for Quantum Light Generation

This thesis presents work on a series of devices for the generation of photonic quantum states based on self-assembled InAs quantum dots, which are among the most technologically mature candidates for practical quantum photonic applications due to their high internal quantum efficiency, narrow linewidth, tunability and straightforward integration with photonic and electric components. The primary results presented concern sources of multi-photon entangled states and single-photon sources with high repetition rate, both of which are crucial components for emerging photonic quantum technologies. First, we propose a scheme for the sequential generation of entangled photon chains by resonant scattering of a laser field on a single charged particle in a cavity-enhanced quantum dot. The charge has an associated spin that can determine the time bin of a photon, allowing for information encoding in this degree of freedom. We demonstrate coherent operations on this spin and realize a proof-of-principle experiment of the proposed scheme by showing that the time bin of a single-photon is dependent on the measured state of the trapped spin. The second main avenue of work investigates the effects of a surface acoustic wave, a mechanical displacement wave confined to the surface of a substrate, on the optical properties of quantum dots. In particular, we exploit the dynamic acoustically-induced tuning of the emission energy to modulate the Purcell effect in a pillar microcavity. Under resonant optical excitation we demonstrate the conversion of the continuous wave laser into a pulsed single-photon stream inheriting the acoustic frequency of 1 GHz as the repetition rate. High resolution spectroscopy reveals the presence of narrow sidebands in the emission spectrum, whose relative intensity can be controlled by the acoustic power and laser detuning. Furthermore, we develop a platform for analogous in-plane experiments by transferring GaAs membranes hosting quantum dots onto LiNbO3 substrates and patterning them into whispering gallery mode optical resonators. In addition to Purcell enhancement and acoustic tuning of the emission, the devices exhibit strong localized mechanical resonances. Finally, we perform initial experiments on the effects of a surface acoustic wave on the spin of a charge trapped in a quantum dot. We integrate acoustic transducers with charge-tunable diodes, where the charge state of the dot can be precisely controlled by an applied bias voltage, and demonstrate the frustration of optical spin pumping by the acoustic wave.This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 642688

Proceedings of the 22nd Conference on Formal Methods in Computer-Aided Design – FMCAD 2022

The Conference on Formal Methods in Computer-Aided Design (FMCAD) is an annual conference on the theory and applications of formal methods in hardware and system verification. FMCAD provides a leading forum to researchers in academia and industry for presenting and discussing groundbreaking methods, technologies, theoretical results, and tools for reasoning formally about computing systems. FMCAD covers formal aspects of computer-aided system design including verification, specification, synthesis, and testing

Development of an Underground Mine Scout Robot

Despite increased safety and improved technology in the mining industry, fatal disasters still occur. Robots have the potential to be an invaluable resource for search and rescue teams to scout dangerous or difficult situations. Existing underground mine search and rescue robots have demonstrated limited success. Identified through literature, the two primary concerns are unreliable locomotion systems and a lack of underground mine environment consideration. HADES, an underground mine disaster scout, addresses these issues with a unique chassis and novel locomotion. A system level design is carried out, addressing the difficulties of underground mine environments. To operate in an explosive atmosphere, a purge and pressurisation system is applied to a fibre glass chassis, with intrinsic safety incorporated into the sensor design. To prevent dust, dirt and water damaging the electronics, ingress protection is applied through sealing. The chassis is invertible, with a low centre of gravity and a roll-axis pivot. This chassis design, in combination with spoked-wheels allows traversal of the debris and rubble of a disaster site. Electrochemical gas sensors are incorporated, along with RGB-D cameras, two-way audio and various other environment sensors. A communication system combining a tether and mesh network is designed, with wireless nodes to increase wireless range and reliability. Electronic hardware and software control are implemented to produce an operational scout robot. HADES is 0.7 × 0.6 × 0.4 m, with a sealed IP65 chassis. The locomotion system is robust and effective, able to traverse most debris and rubble, as tested on the university grounds and at a clean landfill. Bottoming out is the only problem encountered, but can be avoided by approaching obstacles correctly. The motor drive system is able to drive HADES at walking speed (1.4 m/s) and it provides more torque than traction allows. Six Lithium-Polymer batteries enable 2 hours 28 minutes of continuous operation. At 20 kg and ~$7000, HADES is a portable, inexpensive scout robot for underground mine disasters

Volume 2 – Conference

We are pleased to present the conference proceedings for the 12th edition of the International Fluid Power Conference (IFK). The IFK is one of the world’s most significant scientific conferences on fluid power control technology and systems. It offers a common platform for the presentation and discussion of trends and innovations to manufacturers, users and scientists. The Chair of Fluid-Mechatronic Systems at the TU Dresden is organizing and hosting the IFK for the sixth time. Supporting hosts are the Fluid Power Association of the German Engineering Federation (VDMA), Dresdner Verein zur Förderung der Fluidtechnik e. V. (DVF) and GWT-TUD GmbH. The organization and the conference location alternates every two years between the Chair of Fluid-Mechatronic Systems in Dresden and the Institute for Fluid Power Drives and Systems in Aachen. The symposium on the first day is dedicated to presentations focused on methodology and fundamental research. The two following conference days offer a wide variety of application and technology orientated papers about the latest state of the art in fluid power. It is this combination that makes the IFK a unique and excellent forum for the exchange of academic research and industrial application experience. A simultaneously ongoing exhibition offers the possibility to get product information and to have individual talks with manufacturers. The theme of the 12th IFK is “Fluid Power – Future Technology”, covering topics that enable the development of 5G-ready, cost-efficient and demand-driven structures, as well as individual decentralized drives. Another topic is the real-time data exchange that allows the application of numerous predictive maintenance strategies, which will significantly increase the availability of fluid power systems and their elements and ensure their improved lifetime performance. We create an atmosphere for casual exchange by offering a vast frame and cultural program. This includes a get-together, a conference banquet, laboratory festivities and some physical activities such as jogging in Dresden’s old town.:Group 1 | 2: Digital systems Group 3: Novel displacement machines Group 4: Industrial applications Group 5: Components Group 6: Predictive maintenance Group 7: Electro-hydraulic actuatorsDer Download des Gesamtbandes wird erst nach der Konferenz ab 15. Oktober 2020 möglich sein.:Group 1 | 2: Digital systems Group 3: Novel displacement machines Group 4: Industrial applications Group 5: Components Group 6: Predictive maintenance Group 7: Electro-hydraulic actuator