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This thesis presents the measurement of decay-time-dependent 𝐶𝑃 violation in the decays of 𝐵0 → 𝜓(2𝑆)𝐾S0 and 𝐵0 → 𝐽/𝜓𝐾S0 using data collected with the LHCb experiment in 𝑝𝑝 collisions at centre-of-mass energies of 7 TeV and 8 TeV, corresponding to a total integrated luminosity of 3 fb−1. In both considered decay modes, the 𝐾S0 meson is reconstructed from two charged pions, while the 𝜓(2𝑆) meson is reconstructed from two muons, whereas the 𝐽/𝜓 meson is reconstructed from...
The sensitive detection of different biochemical species is of great interest both for the fundamental research and for practical applications concerning the disease diagnostics and drug screening. The high demand in selective, sensitive, fast and low-cost diagnostic techniques has resulted in the rapid development of various-types biochemical sensors (biosensors). Being analytical devices for the qualitative or/and quantitative determination of biological targets, biosensors usually consist ...
In this thesis, the production of a single top quark in association with a Higgs boson (tH) is studied at √s = 13 TeV in the H → γγ decay channel at the ATLAS experiment. Similar to the production of a Higgs boson in association with a top-antitop quark pair (ttH), tH production allows for a direct measurement of the Yukawa coupling, Yt, of the top quark. Due to a destructive interference in tH production, it also provides sensitivity to negative values of the coupling strength modifier κt = ...
This thesis discusses two analyses of rareBmeson decays that are sensitive to effectsbeyond the Standard Model of particles physics. Both measurements are based on theLHCb Run 1 data sample of proton-proton collisions corresponding to an integratedluminosity of3 fb−1recorded at centre-of-mass energies of 7 and 8 TeV.The first measurement is a search for light scalar particles inB0(s)→μ+μ−μ+μ−decays. Additionally to the Standard Model contributions without intermediateresonances, a specific s...
In this work, several types of biosensors are fabricated, characterized, and utilized for the reliable and accurate detection of speci c biomolecules that playing a crucial role in biochemical processes inside the human organism. During the work, di erent types of biosensing techniques, including whispering-gallerymode (WGM) resonators and eld-e ect transistors (FETs), as well as electrolyteinsulator- semiconductor (EIS) sensors were introduced and used as highly sensitive tools to stu...
Coherent optical spectroscopy such as four-wave mixing and photon echo generation deliver rich information on the energy levels involved in optical transitions through the analysis of polarization of the coherent response. In semiconductors, it can be applied to distinguish between different exciton complexes, which is a highly non-trivial problem in optical spectroscopy. We develop a simple approach based on photon echo polarimetry, in which polar plots of the photon echo amplitude are measu...
This thesis focuses on fourth-order spin correlation functions in semi-conductor quantum dots. Widely studied are the second order spin noise power spectrum and its counterpart in the time domain. However, the information extracted from the second order correlation function is limited, and it stands to reason that higher order correlators carry additional physics. The best and most accessible option to study higher order statistics are fourth order correlators. These can be observe...
An action potential is typically described as a purely electrical change that propagates along the membrane of excitable cells. However, recent experiments have demonstrated that non-linear acoustic pulses that propagate along lipid interfaces and traverse the melting transition, share many similar properties with action potentials. Despite the striking experimental similarities, a comprehensive theoretical study of acoustic pulses in lipid systems is still lacking. Here we demonstrate that a...
In der heutigen Zeit werden komplexe Probleme zumeist durch aufwendige Algorithmen und unter Zuhilfenahme fortgeschrittener Computersysteme gelöst, die jedoch insofern limitiert sind, als dass sie nur eine gewisse Komplexität im Bezug auf die Größe der zu lösenden Probleme erlauben. Steigt der Rechenaufwand nichtlinear mit der Zahl der Eingabeparameter, so kommen selbst hochmoderne Technologien an ihre Grenzen. Eine Alternative zur Berechnung komplexer Probleme ist das Maßschneidern eines phy...
The lead halide perovskites demonstrate huge potential for optoelectronic applications, high energy radiation detectors, light emitting devices and solar energy harvesting. Those materials exhibit strong spin-orbit coupling enabling efficient optical orientation of carrier spins in perovskite-based devices with performance controlled by a magnetic field. Here we show that elaborated time-resolved spectroscopy involving strong magnetic fields can be successfully used for perovskites. We perfor...
Die vorliegende Dissertation behandelt den Einfluss neuer Physik auf die Messungen aktueller Neutrino-Oszillations-Experimente. Insbesondere wird eine neue modellunabhängige Methode zur Analyse der CP-Verletzung in Neutrino Oszillationen entwickelt, die auf Unitaritäts-Argumenten beruht. Es wird gezeigt, dass aktuelle Experimente wie T2K oder NOvA in der Lage sind, den Parameter-Bereich für viele Modelle stark einzuschränken. Durch Einbeziehen der Materie-Effekte in diese neue Methode ergeben...
Das Verständnis und die Manipulation der Elektronenspindynamik und des Transports in niedrigdimensionalen Halbleiter-Nanostrukturen ist eine Schlüsselanforderung für funktionale Quantentechnologien. In dieser Arbeit wird ein zeit- und ortsaufgelöstes magneto-optisches Kerr-Mikroskop eingesetzt. Dieses ermöglicht es die Wirkung von impulsabhängigen effektiven Magnetfeldern auf die Spin-Dynamik eines zweidimensionalen Elektronengases in GaAs und CdTe Quantentrögen mit hoher Ladungsträgerm...
Applying small-angle X-ray scattering in combination with liquid-state theory, we determined the intermolecular interaction potential, V(r), of dense lysozyme solutions, which governs the spatial distribution of the protein molecules and the location of its liquid−liquid phase separation (LLPS) region, in various crowding environments and in presence of natural osmolyte mixtures occurring within cells of organisms that thrive under extreme environmental conditions. The deep-sea osmolyte trime...
Super-resolution imaging has introduced new capabilities to investigate processes at the nanometer scale by optical means. However, most super-resolution techniques require either sparse excitation of few emitters or analysis of high-order cumulants in order to identify several emitters in close vicinity. Here, we present an approach that draws upon methods from quantum optics to perform localization super-resolution imaging of densely packed emitters and determine their number automatically:...
The Dortmund Low Background Facility is a highly sensitive gamma ray spectrometry system, operated in a low-background environment, which enables the measurement of traces of radioactivity with high precision. A HPGe detector is set up within an artificial overburden, equivalent to 10 meters of water. This outer shielding reduces the contribution from cosmic muons during the measurement. Signals induced by cosmic muons that penetrate this shielding are suppressed by an active cosmic muon v...
Pencil beam scanning (PBS) proton therapy is due to its steep dose gradients a promising treatment option for many cancer patients, particularly if the tumour is surrounded by critical organs. Currently, organ motion often poses an obstacle for the irradiation of tumours in the thorax or abdomen since the interference of pencil beam and tumour motion can lead to distortions of the intended dose distribution and requires dedicated motion mitigation techniques. A technique which has been recomm...
Für miniaturisierte Analysesysteme stellen Mikroplasmen eine effiziente Anregungs- oder Ionisierungsmethode dar. Eine Charakterisierung der Plasmaeigenschaften sowie eine Aufklärung der plasmachemischen Prozesse und Mechanismen sind hierfür unerlässlich. In der vorliegenden Arbeit werden die Eigenschaften von Mikrohohlkathodenentladungen (MHCD) für die Analyse von gasförmigen und ein Mikroplasma mit flüssiger Elektrode (LE-DBD) für die Analyse von flüssigen Proben mittels emissionsspektroskop...
Wasser und wässrige Systeme spielen in der Natur und Technik eine signifikante Rolle, da die meisten biologischen und chemischen Prozesse in wässriger Umgebung stattfinden. Tritt eine wässrige Lösung in Kontakt zu einem Festkörper, entsteht eine fest-flüssig-Grenzfläche, an welcher in Wasser gelöste Moleküle bevorzugt adsorbieren können. Im Rahmen dieser Arbeit wurden mittels Röntgenreflektivität (X-ray Reflectivity, XRR) in-situ Einflüsse diverser Parameter auf den Adsorptionsprozess an der ...