Discovery and properties of hybrid materials for potential applications in quantum information science
Date
2022
Authors
Lundgren, Crystal J., author
Neilson, James R, advisor
Prieto, Amy, committee member
Buchanan, Kristen, committee member
Journal Title
Journal ISSN
Volume Title
Abstract
Hybrid halide perovskites and their derivatives are sought after for their unique optoelectronic properties, ease of preparation, and highly tunable structure. Some conjugated π-system containing hybrid halide semiconductors derived from hybrid perovskites show a unique primary electronic transition from the inorganic layer (halide) states to the organic layer (π∗) states. This type of charge-transfer semiconductor demonstrates a quantum two-level system between these frontier orbitals, suggesting that these materials may be useful as qubits in quantum computation. For a material to be suitable for a qubit, it must contain a quantum two-level system that can be char- acterized via optically adressable emission. Here, a new family of hybrid halide semiconductors containing 4-amino-1,2,4-triazole (4AMTZ) are discovered. Chapter 2 discusses the synthesis and characterization of 4AMTZBiI4. The crystal structure of 4AMTZBiI4 is solved and con rmed with powder X-ray diffraction. Photoluminescence studies reveal that there is no optically addressable emission from this system, and the iodide congener is thus not usable as a qubit. Chapter 3 discusses the synthesis and photoluminescence emission spectra of 4AMTZBiBr4 and 4AMTZBiCl4. These studies reveal emission from both the chloride and bromide congeners at T = 77 K that is likely due to the primary charge transfer between the halide and organic states based on the blue shifting of 4AMTZBiBr4 (475 nm) relative to that of 4AMTZBiCl4 (415 nm). Another region of emission observed in both 4AMTZBiBr4 and 4AMTZBiCl4 is centered at 660 nm. This region of emission is not shifted between the halide congeners, suggesting the presence of an emissive self- trapped exciton localized on the inorganic lattice. Though these materials emit at T=77K, there is no optically addressable emission at room temperature.