Methods for treating superconducting cavities
A system and method for treating a cavity comprises arranging a niobium structure in a coating chamber, the coating chamber being arranged inside a furnace, coating the niobium structure with tin thereby forming an Nb 3 Sn layer on the niobium structure, and doping the Nb 3 Sn layer with nitrogen, thereby forming a nitrogen doped Nb 3 Sn layer on the niobium structure.
1. A method comprising:
arranging a niobium structure in a coating chamber;
coating the niobium structure with tin;
forming an Nb 3 Sn layer on the niobium structure;
doping the Nb 3 Sn layer with nitrogen, wherein doping the Nb 3 Sn layer with nitrogen further comprises:
pressurizing a volume holding the Nb 3 Sn layer with nitrogen gas; and
leaving the Nb 3 Sn layer in the nitrogen gas for at least 1 hour.
2. The method of claim 1 wherein a pressure of the volume holding the Nb 3 Sn layer with the nitrogen gas is at least 1 mTorr and at most 1 Torr.
3. The method of claim 1 further comprising:
cooling the niobium structure after leaving the Nb 3 Sn layer in the nitrogen gas for at least 1 hour.
4. The method of claim 3 further comprising:
venting the volume holding the Nb 3 Sn layer after cooling the niobium structure.
5. The method of claim 1 further comprising:
degassing the coating chamber before coating the niobium structure with tin.
6. The method of claim 5 further comprising:
nucleating the niobium structure after the coating chamber is degassed.
7. The method of claim 1 further comprising:
annealing the niobium structure such that unreacted tin on a surface of the niobium structure evaporates.
8. The method of claim 1 wherein the niobium structure comprises a superconducting radiofrequency cavity.