Field-editing technology for quantum materials synthesis using a magnetic field laser furnace

Patent metadata

Field	Value
Publication number	US-11873573-B2
Application number	US-202117794108-A
Country	US
Kind code	B2
Filing date	Jan 21, 2021
Priority date	Jan 22, 2020
Publication date	Jan 16, 2024
Grant date	Jan 16, 2024

Abstract

Various embodiments include a device for producing structurally modified materials. In some embodiments, the device includes a floating zone furnace which holds a feed rod in contact with seed crystal. One or more laser diodes are then used to heat a portion of the feed rod and cause it to transition to a molten state. A magnetic field is applied to the floating zone to change the underlying crystal structure of the material as it solidifies upon exiting the floating zone. In some instances, the changes may include manipulating the bond angle of the crystal structure or altering the unit cell volume of the crystal. Changes in the crystal structure directly affect the electrical resistivity and/or the magnetization and other physical properties of the crystal.

First claim

What is claimed is:

1. A method for producing structurally modified crystals, the method comprising:
focusing light emitted by one or more laser diodes at a floating zone to heat a portion of a feed rod to a molten state within the floating zone while in contact with a seed crystal, wherein the portion of the feed rod comprises a composition of matter having strong spin-orbit interactions and multiple nearly degenerate states;
applying a magnetic field from a magnet to the floating zone to modify a crystal structure of the portion of the feed rod within the floating zone as the portion of the feed rod solidifies from the molten state to a solid state upon exiting the floating zone; and
insulating the magnet from heat radiated from the floating zone.

2. The method of claim 1 , wherein insulating the magnet from the heat radiated from the floating zone comprises removing a total amount of heat from the floating zone equal to a total amount of heat applied to the floating zone by the one or more laser diodes.

3. The method of claim 1 , wherein the magnet is a superconductive magnet operating at a temperature below a critical temperature of the superconductive magnet.

4. The method of claim 1 , wherein insulating the magnet from the heat radiated from the floating zone is performed by a heat sink positioned between the floating zone and the magnet to prevent transfer of heat between the floating zone and the magnet.

5. The method of claim 4 , wherein the heat sink is operatively coupled to a refrigeration system.

6. The method of claim 1 , further comprising reflecting, through use of one or more radiation shields, at least a portion of the heat radiated from the floating zone, back to the floating zone.

7. The method of claim 1 , further comprising creating a vacuum to surround the floating zone.

8. The method of claim 1 , wherein the composition of matter is a compound comprising a 4d or 5d transition metal.

9. A method for producing structurally modified crystals, the method comprising:
focusing light emitted by one or more laser diodes at a metal crucible within a molten zone to heat material within the metal crucible to a molten state;
applying a magnetic field from a magnet to the molten zone to modify a crystal structure of the material within the metal crucible as it solidifies as a temperature of the metal crucible is lowered; and
insulating the magnet from heat radiated from the molten zone.

10. A system for producing structurally modified crystals, wherein the system is configurable to create a molten zone within the system in a first configuration and is configurable to create a floating zone within the system in a second configuration, the system comprising:
one or more laser diodes configured to apply thermal energy to material within either the floating zone or a metal crucible within the molten zone, transitioning the material to a molten state conducive for crystal growth;
a magnet configured to generate a magnetic field within the molten zone or the floating zone to modify a crystal structure of the material as the material solidifies from the molten state to a solid state upon exiting the floating zone, or as a temperature of the molten zone is lowered; and
an insulation system comprising a heat sink and one or more passive radiation shields positioned between the molten zone and the magnet.

11. The system of claim 10 , wherein the magnet is a superconductive magnet operating at a temperature below a critical temperature of the superconductive magnet.

12. The system of claim 10 , wherein the heat sink is operatively coupled to a refrigeration system.

13. The system of claim 10 , wherein the one or more radiation shields are configured to reflect at least a portion of the heat radiated from the molten zone or the floating zone, back to the molten zone or the floating zone.

14. The system of claim 10 , further comprising a region of vacuum surrounding the molten zone or the floating zone for thermal insulation between the molten zone or the floating zone and the magnet.

15. The system of claim 10 , wherein the material comprises a rotating feed rod and a seed crystal, the rotating feed rod configured to absorb thermal energy supplied by the one or more laser diodes within the floating zone, and the seed crystal configured to initiate crystal growth.

16. The system of claim 10 , wherein a total thermal energy supplied by the one or more laser diodes is equal to a total amount of thermal energy removed by the insulation system.

17. The system of claim 10 , further comprising a vacuum chamber, the vacuum chamber enclosing at least the magnet, the one or more laser diodes, the molten zone, and the insulation system.

18. The system of claim 10 wherein the material comprises a composition of matter having strong spin-orbit interactions and multiple nearly degenerate states.

19. The system of claim 18 , wherein the composition of matter is a compound comprising a 4d or 5d transition metal.

Assignees

• Univ Colorado Regents

Inventors

• Cao Gang

Classifications

• C30B13/30 Primary

  Stabilisation or shape controlling of the molten zone, e.g. by concentrators, by electromagnetic fields; Controlling the section of the crystal · CPC title

• C30B13/24

  using electromagnetic waves · CPC title

• C30B29/22 Primary

  Complex oxides · CPC title

• C30B30/04

  using magnetic fields · CPC title

• H01F6/04

  Cooling · CPC title