METHOD OF STUDYING CHIRALITY CONTROLLED ARTIFICIAL KAGOME SPIN ICE BUILDING BLOCKS

• US 20120171619A1
• Filed: 04/15/2011
• Published: 07/05/2012
• Est. Priority Date: 04/15/2010
• Status: Active Grant

• Current Assignee: Paul Scherrer-Institut (Schweizerische Eidgenossenschaft)
• Original Assignee: Paul Scherrer-Institut (Schweizerische Eidgenossenschaft)
• Inventors: Heyderman, Laura, Mengotti, Elena, Braun, Hans-Benjamin, Zanin, Danilo, Chopdekar, Rajesh, Hügli, Remo, Duff, Gerard
• Granted Patent: US 8,415,086 B2
• Time in Patent Office: Days
• US Class Current: 430/296
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites

Abstract

A method is provided for achieving low energy states for the study of chirality kagome spin ice structures, the method having the steps of providing a silicon substrate; spin coating a polymethyl acrylate resist on said silicon substrate; providing an electron beam writer; exposing said coated substrate to an electron beam from said electron beam writer; positioning more than one thin island ferromagnetic island structure along a honeycomb lattice of said kagome spin ice component, wherein said positioning being along a determined magnetization direction of said lattice and wherein said island structures providing a mechanism in which chirality is controlled.

Claims

1. A method for achieving low energy states of functionally coupled islands of a functional material, said functionally coupled island being places within a chirality kagome spin ice structure comprising a honeycomb lattice ring structure, each ring structure having six axis declined by an angle of about 60°

one axis to the other, comprising the steps of;

a) providing a silicon substrate;

b) coating a photoresist material, such as a polymethyl acrylate resist, on said silicon substrate;

c) providing an electron beam writer or a photon beam writer;

d) exposing said coated substrate to an electron beam from said electron beam writer or to a photon beam of said photon beam writer, whereby said exposing forms geometric configuration being a kagome ring component having at least one ring structure;

thereby breaking monomer chains of the polymethyl acrylate resist in said exposed region;

e) removing the broken monomer chains in order to achieve void islands and positioning in a variety of said void islands more than one functionally coupled island, each of the functionally coupled islands being oriented along one of the six axis of the honeycomb lattice ring structure of said kagome spin ice component,wherein the functionally coupled islands are substantially identical in length but differ in width;

f) said functionally coupled island structures providing a mechanism in which chirality is controlled according to the physical property of the functional material in the functionally coupled islands.

2. The method of claim 1 wherein said physical property of the functional material is selected from a group consisting of:

a) magnetic dipolar orientation providing a magnetic dipolar coupling;

b) electric dipolar orientation providing an electrical dipolar coupling;

c) ferro-electric orientation providing a ferro-electrical coupling;

d) filled vesicles interlinked by springs with tunable spring constants providing a mechanical coupling;

e) molecular orientation providing physical binding coupling;

f) molecular charge or spin orientation providing physical binding coupling as well;

g) chemical binding status providing coupling by the available coupling links; and

h) light absorption polarization providing a coupling on plasmonic interactions through the supporting surface or matrix.

3. The method of claim 1 wherein said island structures are separated by a distance of about 500 nm.

4. The method of claim 1 wherein said island structures impart an interaction energy of 10⁻

18 J. between nearest structures.

5. The method of claim 1 wherein said island structures have a constant length.

6. The method of claim 1 wherein vortex chirality of a kagome spin ice component is increased with size change of said functionally coupled islands.

7. The method of claim 6 wherein the width of the functionally coupled islands within the honeycomb lattice ring structure of said kagome spin ice component is alternating in order to avoid that two adjacent island have the same width.

8. The method of claim 6 wherein a first subgroup of said island structures have a first width and a second subgroup of said island structure have a second width, wherein the first width is greater than the second width.

9. The method of claim 6 wherein the first width ranges from 100 to 500 nm and the second width ranges from 50 to 200 nm;

thereby observing that the first width has to be greater that the second width.