Systems and methods for quantum dot on nanoplatelet heterostructures with tunable emission in the shortwave infrared

Patent metadata

Field	Value
Publication number	US-12031075-B2
Application number	US-202117465444-A
Country	US
Kind code	B2
Filing date	Sep 2, 2021
Priority date	Sep 2, 2020
Publication date	Jul 9, 2024
Grant date	Jul 9, 2024

Abstract

Many embodiments implement quantum confined nanoplatelets (NPLs) that can be induced to emit bright and tunable infrared emission from attached quantum dot (QD). Some embodiments provide mesoscale NPLs with a largest dimension of greater than 1 micron. Certain embodiments provide methods for growing mesoscale NPLs and QD on mesoscale NPLs heterostructures. Several embodiments provide near unity energy transfer from NPLs to QDs, which can quench NPL emission and emit with high quantum yield through the shortwave infrared. The QD defect emission can be kinetically tunable, enabling controlled mid-gap emission from NPLs.

First claim

What is claimed is:

1. A tunable light emitter comprising:
a nanoplatelet heterostructure, wherein the nanoplatelet heterostructure comprises at least two monolayers of a II-VI semiconductor material; and
at least one quantum dot on a first surface of the nanoplatelet heterostructure;
wherein the at least one quantum dot tunes emission of the nanoplatelet heterostructure and the nanoplatelet heterostructure emits in wavelength range from 900 nm to 1500 nm.

2. The tunable light emitter of claim 1 , wherein the nanoplatelet heterostructure is a two-dimensional structure with quantum confinement along its integer atomic thickness.

3. The tunable light emitter of claim 1 , wherein the II-VI semiconductor material is mercury chalcogenide or cadmium chalcogenide, wherein chalcogenide is selected from the group consisting of sulfide, selenide, and telluride.

4. The tunable light emitter of claim 1 , wherein the nanoplatelet heterostructure comprises at least two monolayers of mercury selenide, three monolayers of mercury selenide, two monolayers of mercury telluride, three monolayers of mercury telluride, two monolayers of cadmium selenide, three monolayers of cadmium selenide, four monolayers of cadmium selenide, five monolayers of cadmium selenide, two monolayers of cadmium telluride, or three monolayers of cadmium telluride.

5. The tunable light emitter of claim 1 , wherein the light emitter has a quantum yield of greater than 30%.

6. The tunable light emitter of claim 1 , wherein the nanoplatelet heterostructure has a lateral dimension of at least 100 nanometers.

7. The tunable light emitter of claim 6 , wherein the nanoplatelet heterostructure has a lateral dimension of at least 1 micron.

8. The tunable light emitter of claim 1 , wherein the nanoplatelet heterostructure has a surface area from 6×10 5 nm 2 to 1×10 6 nm 2 .

9. The tunable light emitter of claim 1 , wherein the at least one quantum dot is grown on the first surface of the nanoplatelet heterostructure in-situ or ex-situ.

10. The tunable light emitter of claim 1 , wherein the at least one quantum dot comprises a II-VI semiconductor material.

11. The tunable light emitter of claim 10 , wherein the II-VI semiconductor material is mercury chalcogenide or cadmium chalcogenide, wherein chalcogenide is selected from the group consisting of sulfides, selenides, and tellurides.

12. A method of synthesizing a nanoplatelet heterostructure, comprising:
providing at least one II-VI semiconductor seed, wherein the seed comprises at least one nanoplatelet;
suspending the at least one II-VI semiconductor seed in a solution;
adding at least one metal precursor in the solution;
adding at least one chalcogen precursor to the solution at an injection rate;
heating the solution to at least 180° C.;
cooling the heated solution; and
precipitating the nanoplatelet heterostructure;
wherein the nanoplatelet heterostructure has a lateral dimension of at least 1 micron; and
wherein the chalcogen precursor is tri-n-octylphosphine sulfide or tri-n-octylphosphine telluride.

13. The method of claim 12 , wherein the injection rate is less than 1 mL/hour.

14. The method of claim 13 , wherein the injection rate is less than 0.55 mL/hour.

15. The method of claim 12 , wherein the solution is heated to a temperature between 220° C. to 240° C.

16. The method of claim 12 , wherein the metal precursor is cadmium precursor or mercury precursor.

17. The method of claim 12 , wherein the at least one II-VI semiconductor seed is mercury chalcogenide or cadmium chalcogenide, wherein chalcogenide is selected from the group consisting of sulfides, selenides, and tellurides.

Assignees

• Univ California

Inventors

• Caram Justin
• Tenney Stephanie

Classifications

• B82Y20/00

  Nanooptics, e.g. quantum optics or photonic crystals · CPC title

• C01P2004/24

  Nanoplates, i.e. plate-like particles with a thickness from 1-100 nanometer · CPC title

• C01P2006/60

  Optical properties, e.g. expressed in CIELAB-values · CPC title

• B82Y40/00

  Manufacture or treatment of nanostructures · CPC title

• B82Y30/00

  Nanotechnology for materials or surface science, e.g. nanocomposites · CPC title