Quantum Dynamical Phenomena in Non-Hermitian and Magnomechanical Systems

In this dissertation, we have investigated quantum dynamics via three case studies. First, we studied a system of two coupled waveguides respectively carrying optical damping and optical gain in addition to squeezing elements in one or both waveguides. Such a system is expected to generate highly entangled light fields in the two waveguides. We, however, show that the degree of the created entanglement is significantly affected by the quantum noises associated with the amplification and dissipation. Because of the noise effect, one can only have nonzero entanglement for a limited time interval. Second, we generalized the first project by considering the gain saturation effect. The nonclassical properties of light are highly relevant to the gain saturation that influences the quantum noise. We explained the impact of gain saturation on a quantum light field dynamically evolving in the coupled system. In contrast to the ideal situation without gain saturation, one can achieve a steady state under the gain saturation. Moreover, gain saturation reduces the influence of amplification noise and thereby better preserves such quantum features as entanglement. We illustrate the effects of gain saturation by examining the time evolution of theWigner function, the entanglement of the light fields, and the cross-correlation function between the two output modes. Significant differences exist between unsaturated and saturated situations, especially for low photon numbers. Finally, we studied a magnomechanical phonon laser beyond the steady-state that includes a microwave cavity with a ferromagnetic sphere installed in it. The system is simultaneously driven by a microwave field and a constant magnetic field. Using the decomposition of the time evolution operator, we linearize the equations of motion and solve them numerically. Our results show there is an oscillatory population inversion between the optical supermodes. However, it is possible to obtain stimulated phonons with relatively high numbers provided the system is operating in the resonant condition and the power of the drive field is higher than its threshold

Ultracold Rydberg Atoms

This thesis presents a new experimental facility that has been developed in the course of the PhD of the author together with the experimental measurements of the dipole moments for transitions between 5P3/2 and nD5/2 states in Rb atoms, where 20 ≤ n ≤ 48. A laser cooling setup for rubidium atoms was designed and built that allows to produce 3 x 10 atoms at temperature of few microkelvins. A laser system for coherent excitation to Rydberg states was realised that exploits a two-photon ladder excitation scheme. Such setup allowed to directly measure transition dipole moments from the first excited state to high n Rydberg states. The electromagnetically induced transparency and Autler-Townes splitting phenomena were exploited in order to obtain the values of the dipole moments, which were found to be in an excellent agreement with the theoretical values calculated using the quasiclassical approach by our collaborators in Novosibirsk. To the author's knowledge, these are the first direct measurements of such dipole moments. The data shown in the thesis proves the reliability of the measurement method. The obtained results are extremely useful to validate theoretical models and gain insight in the physics of the interactions that will be an object of subsequent studies. The methods presented in the dissertation will be used in the future to detect in a non-destructive way Rydberg-Rydberg interactions within mesoscopic samples

Annual report 2015

Accessions considered in the study. Overview of the material considered in this study. For all materials, the GenBank identifier, the accession and species name as used in this study (Species) as well as their species synonyms used in the donor seed banks or in the NCBI GenBank (Material source/Reference) are provided. The genome symbol, and the country of origin, where the material was originally collected are given. The ploidy level measured in the scope of this study and the information if a herbarium voucher could be deposited in the herbarium of IPK Gatersleben (GAT) is given. Genomic formulas of tetraploids and hexploids are given as “female x male parent”. The genomes of Aegilops taxa follow Kilian et al. [74] and Li et al. [84]. Genome denominations for Hordeum follow Blattner [107] and Bernhardt [12] for the remaining taxa. (XLS 84 kb

URI Undergraduate and Graduate Course Catalog 2022-2023

This is a downloadable PDF version of the University of Rhode Island course catalog.https://digitalcommons.uri.edu/course-catalogs/1074/thumbnail.jp

URI Undergraduate and Graduate Course Catalog 2021-2022

This is a downloadable PDF version of the University of Rhode Island course catalog.https://digitalcommons.uri.edu/course-catalogs/1073/thumbnail.jp

URI Undergraduate and Graduate Course Catalog 2020-2021

This is a downloadable PDF version of the University of Rhode Island course catalog.https://digitalcommons.uri.edu/course-catalogs/1072/thumbnail.jp