Wavelength-Selective Optical Detectors Based on Molecular High-Temperature Superconductor Structures

Wavelength-selective optical detectors which were fabricated by combining molecular materials with high-temperature superconductors are described in this dissertation. Methods for the fabrication and characterization of molecular material/high -temperature superconductor assemblies are developed for the first time. In these structures, effective sensitization of the high-temperature superconductor by the molecular material at specific wavelengths of light is demonstrated. This is the first example in which molecular materials have been combined with high-temperature superconductors to create useful structures. In addition, this is the first time in which energy transfer has been shown to occur over macroscopic distances between molecular and high-temperature -superconducting materials. In this dissertation, the importance of wavelength -selectivity in human vision and detector technologies is first presented. Afterwards, energy- and electron-transfer mechanisms are considered in order to better understand molecule-superconductor interactions. Methods in which molecular and high-temperature-superconducting materials can be combined to fabricate hybrid multilayer structures is developed for the first time. Once suitable techniques were developed, device structures were fabricated, and the optical response properties were characterized. These structures exhibit wavelength-dependent optical enhancement which is shown here to be due to efficient energy transfer by the molecular material to the superconductor. The concept of a mirror-layer effect is introduced as an original strategy to further increase the wavelength -selectivity of these structures. We then investigated experimentally the ability of metal/dielectric structures to enhance the optical response of molecular material/high -temperature superconductor detectors. Further improvement of the optical properties of wavelength-selective molecular material/high-temperature superconductor devices was provided by the development of a prototype three-color sensor. Finally, transient optical response and thermal modeling are utilized to better understand energy-transfer processes in these unique structures.