Download or read book Investigation of coherent microscopic defects inside the tunneling barrier of a Josephson junction written by Grabovskij, Grigorij Jurevic and published by KIT Scientific Publishing. This book was released on 2014-08-07 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: In disordered solids, two-level atomic-tunneling systems are present in large quantity. Only recently, superconducting qubits opened a door for a detection and individual coherent manipulation of such microscopic quantum systems. We succeeded to tune the resonance frequencies of these systems by applying external strain on the qubit chip. Moreover, we observed and analyzed the interaction between two coupled tunneling systems.

Download or read book Resolving locations of defects in superconducting transmon qubits written by Bilmes, Alexander and published by KIT Scientific Publishing. This book was released on 2019-12-09 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Quantum Tunneling of Josephson Vortices in High Impedance Long Junctions written by Wildermuth, Matthias Micha and published by KIT Scientific Publishing. This book was released on 2023-09-11 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the last decades, superconducting devices have emerged as a promising platform for quantum technologies, including quantum sensing and quantum computing. Their key elements are Josephson junctions, which allow for coherent supercurrent tunneling between two weakly linked superconductors. If such a junction is extended in one direction to a long junction, the superconducting phase difference can vary in space and time and may allow for quantized phase windings that drive supercurrent vortices.

Download or read book Investigation of Magnetic Adatoms with Scanning Tunneling Techniques written by Maerkl, Junji Tobias and published by KIT Scientific Publishing. This book was released on 2016-01-20 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this work, magnetic atoms on surfaces are studied with low-temperature scanning tunneling microscopy. Motivated by the idea to use single atoms as magnetic bits, the factors that allow or prevent long-term stability of their magnetic moments are investigated. Lifetimes of up to several minutes can be achieved for the magnetic moments of holmium atoms on a Pt(111) surface, resulting from the combined symmetries of the system. Corresponding theoretical calculations are presented and evaluated.

Download or read book Light Emission from Single Self decoupled Molecules in a Scanning Tunnelling Microscope written by Rai, Vibhuti Narayan and published by KIT Scientific Publishing. This book was released on 2022-10-04 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this work, a clear pathway is presented to achieve well-defined electronically decoupled chromophores from metallic leads without requiring additional insulating layers. To study such self-decoupled molecules, STM equipped with an efficient light detection setup has been used. Results show that the chromophores mounted on tripodal molecular platforms adsorbed on a gold surface present well-defined and efficient electroluminescence down to the single-molecule level.

Download or read book Elastic and Inelastic Scanning Tunneling Spectroscopy on Iron Based Superconductors written by Jandke, Jasmin Maria and published by KIT Scientific Publishing. This book was released on 2019-05-02 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: Within this work, the pairing mechanism of conventional (Pb) and unconventional superconductors (SrFe2(As1-xPx )2 , FeSe, FeSe/STO) was investigated experimentally by means of elastic and inelastic tunneling spectroscopy at temperatures down to 30 mK. The distinction between elastic and inelastic contributions to tunneling data was elaborated. The results help to identify conventional (phonon-mediated) and unconventional (e.g. spin-?uctuation mediated) superconductivity.

Download or read book Schackert Michael PeterScanning Tunneling Spectroscopy on Electron Boson Interactions in Superconductors written by Schackert, Michael Peter and published by KIT Scientific Publishing. This book was released on 2015-03-23 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work describes the experimental study of electron-boson interactions in superconductors by means of inelastic electron tunneling spectroscopy performed with a scanning tunneling microscope (STM) at temperatures below 1 K. This new approach allows the direct measurement of the Eliashberg function of conventional superconductors as demonstrated on lead (Pb) and niobium (Nb). Preparative experiments on unconventional iron-pnictides are presented in the end.

Download or read book Granular aluminium superinductors written by Grünhaupt, Lukas and published by KIT Scientific Publishing. This book was released on 2019-10-24 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Adding nonlinearity to an electromagnetic magnonic quantum hybrid device written by Pfirrmann, Marco and published by KIT Scientific Publishing. This book was released on 2020-10-05 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book, hybrid systems based on yttrium-iron-garnet (YIG), three dimensional microwave cavity resonators, and superconducting transmon qubits, are investigated by continuous wave and pulsed microwave spectroscopy. Limitations to the magnetic linewidth in the quantum regime are identified and coherent exchange between a magnon and a superconducting qubit are demonstrated. Finally, a first step towards a strongly coupled hybrid system containing all three components is demonstrated.

Download or read book Quantum Sensing Experiments with Superconducting Qubits written by Schneider, Andre and published by KIT Scientific Publishing. This book was released on 2021-06-04 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum sensing is a vast and emerging field enabling in-situ studies of quantum systems and hence the development of quantum hybrid systems. This work creates the fundament of direct superconducting-magnetic hybrid systems by developing a local microwave sensing scheme and studying the influence of a static magnetic field on a superconducting qubit. Finally, a proof-of-principle hybrid system is demonstrated, which opens the path towards superconducting-magnetic quantum circuits.

Download or read book Nonlinear Effects in Superconducting Quantum Interference Meta Atoms written by Jung, Philipp and published by KIT Scientific Publishing. This book was released on 2015-01-19 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis deals with the nonlinear aspects of superconducting quantum interference devices (SQUIDs) as magnetic meta-atoms. Such meta-atoms are usually resonant structures that constitute the basic building blocks of a metamaterial with the purpose of giving the material unconventional magnetic properties. Due to their intrinsic nonlinearity, SQUIDs exhibit a number of phenomena such as frequency tunability and multi-stability that make them attractive as controllable meta-atoms.

Download or read book One Dimensional Tunable Josephson Metamaterials written by Butz, Susanne and published by KIT Scientific Publishing. This book was released on 2015-01-07 with total page 155 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents a novel approach to the experimental realization of tunable, superconducting metamaterials. Therefore, conventional resonant meta-atoms are replaced by meta-atoms that contain Josephson junctions, which renders their resonance frequency tunable by an external magnetic field. This tunability is theoretically and experimentally investigated in one-dimensional magnetic and electric metamaterials. For the magnetic metamaterial, the effective, magnetic permeability is determined.

Download or read book Hybrid quantum system based on rare earth doped crystals written by Probst, Sebastian and published by KIT Scientific Publishing. This book was released on 2016-09-05 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hybrid quantum circuits interfacing rare earth spin ensembles with microwave resonators are a promising approach for application as coherent quantum memory and frequency converter. In this thesis, hybrid circuits based on Er and Nd ions doped into Y?SiO? and YAlO? crystals are investigated by optical and on-chip microwave spectroscopy. Coherent strong coupling between the microwave resonator and spin ensemble as well as a multimode memory for weak coherent microwave pulses are demonstrated.

Download or read book Local Probing of a Superconductor s Quasiparticles and Bosonic Excitations with a Scanning Tunnelling Microscope written by Gozlinski, Thomas and published by KIT Scientific Publishing. This book was released on 2023-03-24 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt: Complementary to scattering techniques, scanning tunnelling microscopy provides atomic-scale real space information about a material's electronic state of matter. State-of-the-art designs of a scanning tunnelling microscope (STM) allow measurements at millikelvin temperatures with unprecedented energy resolution. Therefore, this instrument excels in probing the superconducting state at low temperatures and especially its local quasiparticle excitations as well as bosonic degrees of freedom.

Download or read book Molecular Motor Based on Single Chiral Tripodal Molecules Studied with STM written by Skolaut, Julian and published by KIT Scientific Publishing. This book was released on 2023-09-14 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work presents a single molecular motor driven by the current in an STM. Its chiral functional group is supposed to perform a rotation in a preferred direction, proven by Binomial tests to be statistically significant. The rotation is proposedly driven by the chiral-induced spin selectivity effect (CISS). However, the studies of the rotation on the dependence on the lateral tip position, voltage and current indicate that he CISS is unlikely to cause the preferred rotation direction.

Download or read book STM Characterization of Phenylene Ethynylene Oligomers on Au 111 and their Integration into Carbon Nanotube Nanogaps written by Thiele, Cornelius and published by KIT Scientific Publishing. This book was released on 2014-08-05 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: Molecular electronics requires both profound knowledge of a molecule's structure and functionality on a surface and controlled positioning between electrodes with nanometer-sized gaps. In the first part of this work, a detailed scanning tunneling microscope study of two variants of oligo(phenylene ethynylene) molecules is presented. In the second part, methods of fabricating carbon nanotube nanogap electrodes as direct contacts to these molecules are explored.

Download or read book Local Investigation of Single Magnetic Molecules with Scanning Tunneling Microscopy written by Chen, Jinjie and published by KIT Scientific Publishing. This book was released on 2019-01-18 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: We worked on different magnetic molecules containing 3d and 4f magnetic centers. Their growth on metallic surfaces, topographies, spin states, magnetic properties and electron transport were locally investigated by using scanning tunneling microscopy (STM) at temperatures down to 30mK. The main achievement of this dissertation reveals the abrupt switching of crystal fields during formation of molecular contacts.