Nitrogen containing single crystal diamond materials optimized for magnetometry applications

Patent metadata

Field	Value
Publication number	US-11396715-B2
Application number	US-201616065526-A
Country	US
Kind code	B2
Filing date	Dec 6, 2016
Priority date	Dec 22, 2015
Publication date	Jul 26, 2022
Grant date	Jul 26, 2022

Abstract

A single crystal diamond material comprising: neutral nitrogen-vacancy defects (NV0); negatively charged nitrogen-vacancy defects (NV−); and single substitutional nitrogen defects (Ns) which transfer their charge to the neutral nitrogen-vacancy defects (NV0) to convert them into the negatively charged nitrogen-vacancy defects (NV), characterized in that the single crystal diamond material has a magnetometry figure of merit (FOM) of at least 2, wherein the magnetometry figure of merit is defined by (I) where R is a ratio of concentrations of negatively charged nitrogen-vacancy defects to neutral nitrogen-vacancy defects ([NV−]/[NV0]), [NV−] is the concentration of negatively charged nitrogen-vacancy defects measured in parts-per-million (ppm) atoms of the single crystal diamond material, [NV0] is a concentration of neutral nitrogen-vacancy defects measured in parts-per-million (ppm) atoms of the single crystal diamond material, and T2′ is a decoherence time of the NV− defects, where T2′ is T2* for DC magnetometry or T2 for AC magnetometry.

First claim

The invention claimed is:

1. A single crystal diamond material comprising:
neutral nitrogen-vacancy defects (NV 0 );
negatively charged nitrogen-vacancy defects (NV − ); and
single substitutional nitrogen defects (N s ) which transfer their charge to the neutral nitrogen-vacancy defects (NV 0 ) to convert them into the negatively charged nitrogen-vacancy defects (NV − ),
characterized in that the single crystal diamond material has a magnetometry figure of merit (FOM) of at least 2, wherein the magnetometry figure of merit is defined by
FOM= √{square root over ([NV − ]× T 2 ′)}

where is a ratio of concentrations of negatively charged nitrogen-vacancy defects to neutral nitrogen-vacancy defects ([NV − ]/[NV 0 ]), [NV − ] is the concentration of negatively charged nitrogen-vacancy defects measured in parts-per-million (ppm) atoms of the single crystal diamond material, [NV 0 ] is a concentration of neutral nitrogen-vacancy defects measured in parts-per-million (ppm) atoms of the single crystal diamond material, and T 2 ′ is a decoherence time of the NV − defects in microseconds, where T 2 ′ is T 2 * for DC magnetometry or T 2 for AC magnetometry.

2. A single crystal diamond material according to claim 1 ,
wherein the FOM is selected from any of at least 3, at least 4, at least 5, at least 6 and at least 7.

3. A single crystal diamond material according to claim 1 ,
wherein R is selected from any of at least 4, at least 5, at least 6, and at least 7.

4. A single crystal diamond material according to claim 1 ,
wherein [NV − ] is selected from any of at least 1.3 ppm, at least 1.5 ppm and at least 1.7 ppm.

5. A single crystal diamond material according to claim 1 ,
wherein T 2 * is selected from any of at least 0.4 μs, at least 0.5 μs, at least 0.6 μs and at least 0.7 μs.

6. A single crystal diamond material according to claim 1 ,
wherein the single crystal diamond material has a total nitrogen concentration selected from any of at least 3 ppm, at least 5 ppm, at least 8 ppm, at least 12 ppm, at least 18 ppm and at least 25 ppm.

7. A single crystal diamond material according to claim 1 ,
wherein the single crystal diamond material is single crystal CVD diamond.

8. A single crystal diamond material according to claim 1 ,
wherein the single crystal diamond material has three orthogonal dimensions of at least 0.5 mm.

9. A single crystal diamond material according to claim 1 ,
wherein the single crystal diamond material has a 15 N concentration which is higher than 0.4% of a total nitrogen concentration in the single crystal diamond material and/or an 15 NV concentration which is higher than 0.4% of a total NV concentration given by 14 NV+ 15 NV.

Assignees

• Element Six Tech Ltd
• Element Six Tech Us Corporation

Inventors

• Lew Wilbur
• Bruce Gregory
• Edmonds Andrew Mark
• Markham Matthew Lee
• Stacey Alastair Douglas
• Dhillon Harpreet Kaur

Classifications

• C30B25/02

  Epitaxial-layer growth · CPC title

• C30B31/20

  Doping by irradiation with electromagnetic waves or by particle radiation · CPC title

• C30B30/04

  using magnetic fields · CPC title

• C30B29/04 Primary

  Diamond · CPC title

• C30B33/04

  using electric or magnetic fields or particle radiation · CPC title