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Title: Passivated niobium cavities

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.

Inventors:
 [1];  [2];  [3]
  1. Yorktown, VA
  2. Lagga Arby, SE
  3. Newport News, VA
Issue Date:
Research Org.:
Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
982424
Patent Number(s):
7151347
Application Number:
11/168,198
Assignee:
Jefferson Science Associates LLC (Newport News, VA)
Patent Classifications (CPCs):
H - ELECTRICITY H01 - BASIC ELECTRIC ELEMENTS H01P - WAVEGUIDES
H - ELECTRICITY H05 - ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR H05H - PLASMA TECHNIQUE
DOE Contract Number:  
AC05-84ER40150
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Myneni, Ganapati Rao, Hjorvarsson, Bjorgvin, and Ciovati, Gianluigi. Passivated niobium cavities. United States: N. p., 2006. Web.
Myneni, Ganapati Rao, Hjorvarsson, Bjorgvin, & Ciovati, Gianluigi. Passivated niobium cavities. United States.
Myneni, Ganapati Rao, Hjorvarsson, Bjorgvin, and Ciovati, Gianluigi. Tue . "Passivated niobium cavities". United States. https://www.osti.gov/servlets/purl/982424.
@article{osti_982424,
title = {Passivated niobium cavities},
author = {Myneni, Ganapati Rao and Hjorvarsson, Bjorgvin and Ciovati, Gianluigi},
abstractNote = {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.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Dec 19 00:00:00 EST 2006},
month = {Tue Dec 19 00:00:00 EST 2006}
}