Gianluigi Ciovati from Yorktown, VA, age 48

Gianluigi Ciovati Phones & Addresses

Passivated Niobium Cavities
view source
US Patent:

7151347, Dec 19, 2006
Filed:

Jun 28, 2005
Appl. No.:

11/168198
Inventors:

Ganapati Rao Myneni - Yorktown VA, US
Bjorgvin Hjorvarsson - Lagga Arby, SE
Gianluigi Ciovati - Newport News VA, US
Assignee:

Jefferson Science Associates LLC - Newport News VA
International Classification:

H01J 25/00
H01J 25/10
US Classification:

315500, 315 541
Abstract:

A niobium cavity exhibiting high quality factors at high gradients is provided by treating a niobium cavity through a process comprising: 1) removing surface oxides by plasma etching or a similar process; 2) removing hydrogen or other gases absorbed in the bulk niobium by high temperature treatment of the cavity under ultra high vacuum to achieve hydrogen outgassing; and 3) assuring the long term chemical stability of the niobium cavity by applying a passivating layer of a superconducting material having a superconducting transition temperature higher than niobium thereby reducing losses from electron (cooper pair) scattering in the near surface region of the interior of the niobium cavity. According to a preferred embodiment, the passivating layer comprises niobium nitride (NbN) applied by reactive sputtering.