Covalently-bound anti-relaxation surface coatings and application in magnetometers

Patent metadata

Field	Value
Publication number	US-11307268-B2
Application number	US-201916679048-A
Country	US
Kind code	B2
Filing date	Nov 8, 2019
Priority date	Dec 18, 2018
Publication date	Apr 19, 2022
Grant date	Apr 19, 2022

Abstract

A magnetometer includes a vapor cell having at least one wall, a chamber defined by the at least one wall, and alkali metal atoms disposed in the chamber to produce an alkali metal vapor in the chamber, wherein the at least one wall includes an oxide-containing interior surface; and an anti-relaxation coating disposed on the oxide-containing interior surface of the at least one wall of the vapor cell, wherein the anti-relaxation coating is a reaction product of the oxide-containing interior surface of the at least one wall with at least one mono- or dichlorosilane compound.

First claim

What is claimed as new and desired to be protected by Letters Patent of the United States is:

1. A magnetometer, comprising:
a vapor cell comprising at least one wall, a chamber defined by the at least one wall, and alkali metal atoms disposed in the chamber to produce an alkali metal vapor in the chamber, wherein the at least one wall comprises an oxide-containing interior surface; and
an anti-relaxation coating disposed on the oxide-containing interior surface of the at least one wall of the vapor cell, wherein the anti-relaxation coating is a reaction product of the oxide-containing interior surface of the at least one wall with at least one mono- or dichlorosilane compound selected from:

wherein x, y, and z, when present, are each independently an integer in a range of 0 to 40.

2. The magnetometer of claim 1 , wherein the at least one mono- or dichlorosilane compound comprises

3. The magnetometer of claim 1 , wherein the at least one mono- or dichlorosilane compound comprises

4. The magnetometer of claim 1 , wherein x, y, and z, when present, are each independently an integer in a range of 5 to 25.

5. The magnetometer of claim 1 , wherein x, y, and z, when present, are equal.

6. The magnetometer of claim 1 , wherein the oxide-containing interior surface comprises silicon dioxide.

7. The magnetometer of claim 1 , wherein the oxide-containing interior surface comprises aluminum oxide.

8. The magnetometer of claim 1 , wherein the vapor cell comprises quartz.

9. The magnetometer of claim 1 , wherein the vapor cell comprises sapphire.

10. The magnetometer of claim 1 , wherein the vapor cell comprises glass.

11. A magnetic field measurement system, comprising:
at least one magnetometer of claim 1 ;
at least one light source configured for directing light to the at least one magnetometer; and
at least one detector configured to receive light that passes through the at least one magnetometer.

12. The magnetic field measurement system of claim 11 , further comprising at least one magnetic field generator configured to produce a magnetic field at the vapor cell of the at least one magnetometer.

13. The magnetic field measurement system of claim 11 , further comprising a computing device coupled to the at least one detector.

14. A method of making the magnetometer of claim 1 , the method comprising:
contacting the oxide-containing interior surface of the at least one wall of the vapor cell with the at least one mono- or dichlorosilane compound; and
reacting the mono- or diclorosilane compound with the oxide-containing interior surface to form an anti-relaxation coating on the oxide-containing interior surface.

15. The method of claim 14 , wherein the at least one mono- or dichlorosilane compound comprises

16. The method of claim 14 , wherein the at least one mono- or dichlorosilane compound comprises

17. The method of claim 14 , wherein the oxide-containing interior surface comprises silicon dioxide.

18. The method of claim 14 , wherein the oxide-containing interior surface comprises aluminum oxide.

19. The method of claim 14 , wherein the vapor cell comprises quartz.

20. The method of claim 14 , wherein the vapor cell comprises sapphire.

Assignees

• Hi Llc

Inventors

• Bhattacharyya Sukanta
• Sobek Daniel

Classifications

• G01R33/028 Primary

  Electrodynamic magnetometers · CPC title

• G01R33/26

  using optical pumping · CPC title

• A61B5/245

  specially adapted for magnetoencephalographic [MEG] signals · CPC title

• G01R33/025

  Compensating stray fields {(G01R33/0017 takes precedence)} · CPC title

• C09D201/10

  containing hydrolysable silane groups · CPC title