Laser gain media fabricated via direct ink writing (DIW) and ceramic processing

Patent metadata

Field	Value
Publication number	US-10840668-B2
Application number	US-201716306865-A
Country	US
Kind code	B2
Filing date	Jun 16, 2017
Priority date	Jun 17, 2016
Publication date	Nov 17, 2020
Grant date	Nov 17, 2020

Abstract

A transparent ceramic optic includes: a lasing region comprising at least one lasing species dopant; and a transparent region transparent to light generated by the lasing species. At least the transparent region is doped with at least one other dopant species such that the lasing region and the transparent region are characterized by a difference in refractive index between the two regions in an amount of about 1.0×10−4 or less. Inventive formulations of inks suitable for fabricating transparent ceramic optics having desirable compositional characteristics such as concentration gradients in desired spatial arrangements, e.g. using additive manufacturing techniques such as direct ink writing and/or extrusion freeform fabrication are also disclosed, along with suitable techniques for forming the transparent ceramic optics from such inks.

First claim

What is claimed is:

1. A composition of matter, comprising a plurality of particles in a thixotropic suspension to form an ink,
wherein the plurality of particles are present in an amount of at least about 20 vol %, and comprise of at least two of:
a first host medium material containing at least one of:
one or more lasing species dopants; and
one or more other dopant species;

an undoped host medium material; and
a second host medium material containing at least one other dopant species; and

a liquid phase present in an amount greater than 20 vol % and less than about 80 vol %, wherein the liquid phase comprises at least one of:
at least one surfactant;
at least one polar organic solvent; and
at least one binder; and

wherein said thixotropic suspension exhibits shear thinning at shear rates of greater than about 1 s −1 and a zero-shear viscosity of greater than about 100 Pa·s.

2. The composition of matter as recited in claim 1 , wherein the host medium material comprises two or more of: Y, Gd, La, Ce, Lu, Sc, Ga, Al and O.

3. The composition of matter as recited in claim 1 , wherein the host medium material comprises particles having a composition characteristic of a garnet structure.

4. The composition of matter as recited in claim 1 , wherein the host medium material is characterized by a formula: M 1 3 M 2 5 O 12 ;
wherein M 1 is a composition comprising one or more components selected from Gd, Y, Lu, Er, Yb and Ce; and
wherein M 2 is a composition comprising one or more components selected from Ga, Sc and Al.

5. The composition of matter as recited in claim 1 , wherein the host medium material is substantially characterized by a formula: Y 3 Al 5 O 12 .

6. The composition of matter as recited in claim 1 , wherein the particles are present in an amount ranging from greater than about 20 vol % to about 70 vol %.

7. The composition of matter as recited in claim 1 , wherein the surfactant is present in an amount ranging from greater than about 0 vol % to about 40 vol % and comprises an organic acid surfactant.

8. The composition of matter as recited in claim 1 , wherein the polar organic solvent is present in an amount ranging from greater than about 10 vol % to about 70 vol % and comprises one or more of: propylene carbonate, di-methoxyethanol, tri-methoxyethanol, tetra-methoxyethanol, water, one or more alcohols, one or more cyclic carbonates, one or more ethylene oxide-based glymes, one or more propylene oxide-based glymes, and one or more propylene glycol-based glymes.

9. The composition of matter as recited in claim 1 , wherein the binder is present in an amount ranging from greater than about 0 vol % to about 60 vol % and comprises one or more of:
polyethylene glycol (PEG) or a glyme thereof;
polypropylene glycol (PPG) or a glyme thereof;
methacrylic acid or a derivative thereof; and
a polymerizable glycol.

10. The composition of matter as recited in claim 1 , wherein the at least one other dopant species comprises one or more of: Lu, La, Ce, Sc and Ga.

11. The composition of matter as recited in claim 1 , wherein the at least one lasing species comprises one or more of: trivalent rare earth ion(s) and transition metal(s).

12. The composition of matter as recited in claim 11 , wherein the trivalent rare earth ion(s) comprise(s) one or more of: Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb.

13. The composition of matter as recited in claim 11 , wherein the transition metal(s) comprise(s) one or more of: Ti, Co, V, Cr, Fe and Ni.

14. A transparent ceramic optic formed from a composition of matter comprising a plurality of particles in a thixotropic suspension to form an ink,
wherein the plurality of particles are present in an amount of at least about 20 vol%, and comprise of at least two of:
a first host medium material containing at least one of:
one or more lasing species dopants; and
one or more other dopant species;

an undoped host medium material; and
a second host medium material containing at least one of the one or more other dopant species; and

a liquid phase present in an amount greater than 20 vol% and less than about 80 vol%, wherein the liquid phase comprises at least one of:
at least one surfactant;
at least one polar organic solvent; and
at least one binder; and

wherein said thixotropic suspension exhibits shear thinning at shear rates of greater than about 1s −1 and a zero-shear viscosity of greater than about 100 Pa·s;
wherein the transparent ceramic optic comprises:
a lasing region comprising the one or more lasing species dopants; and
a transparent region transparent to light generated by the one or more lasing species dopants; and

wherein at least the transparent region is doped with at least one of the one or more other dopant species such that the lasing region and the transparent region are characterized by a difference in refractive index between the two regions in an amount of about 1.0×10 −4 or less.

15. The optic as recited in claim 14 , wherein the at one or more lasing species dopants exhibits a concentration gradient along a radial axis of the optic; and
wherein a concentration of the one or more lasing species dopants reaches a maximum concentration at approximately a midline along an axis of light propagation of the optic, along a longitudinal axis thereof.

16. The optic as recited in claim 15 , wherein the radial concentration gradient exists with respect to a ratio of at least one of the one or more other dopant species.

17. The optic as recited in claim 14 , wherein the lasing region comprises a plurality of discrete transverse sections each respectively comprising either:
different ones of the one or more lasing species dopants;
different amounts of the one or more lasing species dopants; or both.

18. The optic as recited in claim 17 , comprising a gradient with respect to each of the different dopant species between some or all of the discrete transverse sections.

19. The optic as recited in claim 14 , wherein the lasing region is characterized by a longitudinal concentration gradient of the one or more lasing species dopants.

20. The optic as recited in claim 14 , wherein the one or more other dopant species exhibits a radial concentration gradient within at least the transparent region.

21. The optic as recited in claim 20 , wherein the radial concentration gradient extends for a length of at least about ¼ to ½ of a radius of the optic.

22. The optic as recited in claim 14 , wherein the optic exhibits a polycrystalline, cubic phase crystal structure.

23. The optic as recited in claim 14 , wherein the optic exhibits a garnet structure incorporating the one or more lasing species dopants and the one or more other dopant species.

24. The optic as recited in claim 14 , wherein the one or more lasing species dopants comprise(s) one or more of: trivalent rare earth ion(s) and transition metal(s).

25. The optic as recited in claim 24 , wherein the trivalent rare earth ion(s) comprise(s) one or more of: Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb.

26. The optic as recited in claim 24 , wherein the transition metal(s) comprise(s) one or more of: Ti, V, Co, Cr, Fe and Ni.

27. The optic as recited in claim 14 , wherein the one or more other dopant species comprise(s) one or more of: Lu, La, Ce, Sc, and Ga.

28. The optic as recited in claim 14 , further comprisi

Assignees

• L Livermore Nat Security Llc

Inventors

• Payne Stephen A
• Cherepy Nerine J
• Duoss Eric B
• Jones Ivy Krystal
• Seeley Zachary M
• Zhu Cheng

Classifications

• G01B11/06

  for measuring thickness {; e.g. of sheet material (thickness measurement by thermal means G01B21/085)} · CPC title

• H01S3/0612

  Non-homogeneous structure (H01S3/07 takes precedence) · CPC title

• H01S3/08045

  Single-mode emission · CPC title

• H01S3/113

  using intracavity saturable absorbers · CPC title

• H01S3/0941

  of a laser diode · CPC title