High-temperature carbon-based superconductor: B-doped Q-carbon

Patent metadata

Field	Value
Publication number	US-11189774-B2
Application number	US-201816614686-A
Country	US
Kind code	B2
Filing date	May 31, 2018
Priority date	May 31, 2017
Publication date	Nov 30, 2021
Grant date	Nov 30, 2021

Abstract

Certain embodiments involve processes or systems for creating various high-temperature superconductive structures or materials. For example, a method can involve depositing a first layer of boron and a second layer of un-doped amorphous carbon on a substrate. The un-doped amorphous carbon is ferromagnetic. The first layer of boron and the second layer of un-doped amorphous carbon are melted by a laser pulse to form a melted boron-doped amorphous carbon. The melted boron-doped amorphous carbon is quenched to create a quenched boron-doped amorphous carbon that is diamagnetic and superconducting. The quenched melted boron-doped amorphous carbon includes a mixture of sp3 bonded carbon atoms and sp2 bonded carbon atoms and a superconducting transition temperature of the quenched boron-doped amorphous carbon is much higher than diamond and increases based on a boron concentration. Undoped Q-carbon is ferromagnetic with Curie temperature above 500K.

First claim

What is claimed is:

1. A method comprising:
depositing a first layer of boron and a second layer of un-doped amorphous carbon on a substrate, wherein the un-doped amorphous carbon is diamagnetic;
melting the first layer of boron and the second layer of un-doped amorphous carbon by a laser pulse to form a melted boron-doped amorphous carbon; and
quenching the melted boron-doped amorphous carbon to create a quenched boron-doped amorphous carbon that is diamagnetic and superconducting, wherein the quenched melted boron-doped amorphous carbon comprises a mixture of sp3 bonded carbon atoms and sp2 bonded carbon atoms and a superconducting transition temperature (T c ) of the quenched boron-doped amorphous carbon increases based on a boron concentration and is higher than a superconducting transition temperature of diamond.

2. The method of claim 1 , wherein depositing the first layer of boron and the second layer of un-doped amorphous carbon on the substrate comprises:
depositing the first layer of boron or the second layer of un-doped amorphous carbon on the substrate to a thickness between approximately 100 nanometers (nm) and 500 nm at a temperature between approximately 30 degrees Celsius and 300 degrees Celsius and between approximately 1.0E minus 6 torr operating pressure.

3. The method of claim 1 , wherein the superconducting transition temperature of the quenched boron-doped amorphous carbon is at least 35 K and the quenched boron-doped amorphous carbon has an upper critical field of approximately 5.4 T at 0 K.

4. The method of claim 1 , wherein the superconducting transition temperature of the quenched boron-doped amorphous carbon is between 35.5 K and 36.5 K.

5. The method of claim 1 , wherein the superconducting transition temperature of the quenched boron-doped amorphous carbon is between 37 K and 55 K.

6. The method of claim 1 , wherein the superconducting transition temperature of the quenched boron-doped amorphous carbon is at least 55 K.

7. The method of claim 1 , wherein the superconducting transition temperature of the quenched boron-doped amorphous carbon is up to 37 K and the quenched boron-doped amorphous carbon comprises approximately seventeen atomic percent boron atoms.

8. The method of claim 1 , wherein the superconducting transition temperature of the quenched boron-doped amorphous carbon is up to 55 K and the quenched boron-doped amorphous carbon comprises approximately twenty five atomic percent boron atoms.

9. The method of claim 1 , wherein the superconducting transition temperature of the quenched boron-doped amorphous carbon is above 100K and the quenched boron-doped amorphous carbon comprises approximately fifty atomic percent boron atoms.

10. The method of claim 1 , wherein the quenched un-doped amorphous carbon shows ambient temperature ferromagnetism with a Curie temperature above 500 K.

11. The method of claim 1 , wherein the substrate comprises sapphire.

12. A product formed by the method of claim 1 .

13. A method comprising:
depositing a first layer of boron and a second layer of un-doped amorphous carbon on a substrate by:
depositing the first layer of boron or the second layer of un-doped amorphous carbon on the substrate to a thickness between approximately 100 nanometers (nm) and 500 nm;

melting the first layer of boron and the second layer of un-doped amorphous carbon by a laser pulse to form a melted boron-doped amorphous carbon; and
quenching the melted boron-doped amorphous carbon to create a quenched boron-doped amorphous carbon that is diamagnetic and superconducting, wherein the quenched melted boron-doped amorphous carbon comprises a mixture of sp3 bonded carbon atoms and sp2 bonded carbon atoms and wherein a superconducting transition temperature (T c ) of the quenched boron-doped amorphous carbon increases based on a boron concentration and is higher than a superconducting transition temperature of diamond.

14. The method of claim 13 , wherein depositing the first layer of boron and the second layer of amorphous carbon on the substrate further comprises:
depositing the first layer of boron or the second layer of un-doped amorphous carbon on the substrate at a temperature between approximately 30 degrees Celsius and 300 degrees Celsius and between approximately 1.0E minus 6 torr operating pressure.

15. The method of claim 13 , wherein the superconducting transition temperature of the quenched boron-doped amorphous carbon is at least 35 K and the quenched boron-doped amorphous carbon has an upper critical field of approximately 5.4 T at 0 K.

16. The method of claim 13 , wherein the superconducting transition temperature of the quenched boron-doped amorphous carbon is between 35.5 K and 36.5 K.

17. The method of claim 13 , wherein the superconducting transition temperature of the quenched boron-doped amorphous carbon is between 37 K and 55 K.

18. The method of claim 13 , wherein the superconducting transition temperature of the quenched boron-doped amorphous carbon is at least 55 K.

19. The method of claim 13 , wherein the superconducting transition temperature of the quenched boron-doped amorphous carbon is: i) up to 37 K when the quenched boron-doped amorphous carbon comprises approximately seventeen atomic percent boron atoms; ii) up to 55 K when the quenched boron-doped amorphous carbon comprises approximately twenty five atomic percent boron atoms; or iii) above 100K when the quenched boron-doped amorphous carbon comprises approximately fifty atomic percent boron atoms.

20. The method of claim 13 , wherein the quenched un-doped amorphous carbon shows ambient temperature ferromagnetism with a Curie temperature above 500 K.

Assignees

• Univ North Carolina State

Inventors

• Narayan Jagdish

Classifications

• C23C16/56

  After-treatment · CPC title

• C23C16/26 Primary

  Deposition of carbon only · CPC title

• H01L39/249 Primary

  Electricity · mapped topic

• H01L39/12

  Electricity · mapped topic

• H10N60/85

  Superconducting active materials · CPC title