TECHNOLOGICAL ASPECTS OF QUANTUM DECOHERENCE IN SUPERCONDUCTING JOSEPHSON QUBITS

Bruno, Alessandro (2011) TECHNOLOGICAL ASPECTS OF QUANTUM DECOHERENCE IN SUPERCONDUCTING JOSEPHSON QUBITS. [Tesi di dottorato] (Inedito)

Full text disponibile come:

[img]
Preview
PDF - Richiede un editor Pdf del tipo GSview, Xpdf o Adobe Acrobat Reader
9Mb

Abstract

The aim of this thesis was to realize superconducting quantum bits by using novel fabrication techniques and materials in order to enhance the coherence time of the former devices. For the system to be studied we chose the ux-biased phase qubit, which consists of a Josephson junction integrated in a superconducting loop. This qubit realization has some advantages, which make it an ideal test-bed for different fabrication technologies and materials. Relatively large Josephson junctions can be used in the phase qubit realization, which are easy to be fabricated by using standard lithographic technology with the flexibility of employing various fabrication techniques and materials. The coherence of current-generation of superconducting qubits seems to be limited by intrinsic sources of noise and energy loss, related to materials' defects (two-level systems, TLSs) on the surfaces and interfaces of the superconducting lms, and in the bulk of the dielectric films used for the microelectronic realization of the circuits. For this reason, we aimed our research activities on the realization of low loss dielectrics (a-Si:H), on its integration with Josephson junction technologies, on the protection of the superconducting films' surfaces from unwanted contamination, and on the optimization of the circuit design and fabrication processes.

Tipologia di documento:Tesi di dottorato
Parole chiave:Qubits, superconducting resonators, Josephson junctions
Settori scientifico-disciplinari MIUR:Area 02 Scienze fisiche > FIS/03 FISICA DELLA MATERIA
Coordinatori della Scuola di dottorato:
Coordinatore del Corso di dottoratoe-mail (se nota)
Andreone, Antonelloandreone@unina.it
Tutor della Scuola di dottorato:
Tutor del Corso di dottoratoe-mail (se nota)
Lisistskiy, Mikhailm.lisitskiy@cib.na.cnr.it
Cristiano, Robertor.cristiano@cib,.na.cnr.it
Stato del full text:Accessibile
Data:30 Novembre 2011
Numero di pagine:213
Istituzione:Università di Napoli Federico II
Dipartimento o Struttura:Scienze fisiche
Stato dell'Eprint:Inedito
Scuola di dottorato:Ingegneria industriale
Denominazione del dottorato:Tecnologie innovative per materiali, sensori ed imaging
Ciclo di dottorato:24
Numero di sistema:8997
Depositato il:12 Dicembre 2011 13:27
Ultima modifica:23 Aprile 2012 11:31

Solo per gli Amministratori dell'archivio: edita il record