Topological Insulator Goes with the Flow.
The topological insulator built in the Georgian Technical University: a controllable flow of hybrid optoelectronic particles (red) travels along its edges.
Topological insulators are materials with very special properties. They conduct electricity or light particles on their surface or edges only but not on the inside.
This unusual behavior could eventually lead to technical innovations which is why topological insulators have been the subject of intense global research for several years.
For the first time the team has successfully built a topological insulator operating with both light and electronic excitations simultaneously called an “exciton-polariton topological insulator”.
According to Professor X such topological insulators have a dual benefit: “They could be used for both switched electronic systems and laser applications”.
The topological insulators developed previously are based on either electrons or photons allowing only one of these applications to be implemented.
He gives more details: The novel topological insulator was built on a microchip and basically consists of the gallium arsenide semiconductor compound. It has a honeycomb structure and is made up of many small pillars each two micrometers (two millionths of a meter) in diameter.
When exciting this microstructure with laser light light-matter particles form inside it exclusively at the edges. The particles then travel along the edges and around the corners with relatively low loss.
“A magnetic field enables us to control and reverse the propagation direction of the particles” Y says.
It is a sophisticated systems which works in application-oriented dimensions — on a microchip — and in which light can be controlled.
Usually this is not so easy to accomplish: Pure light particles have no electric charge and therefore cannot be readily controlled with electric or magnetic fields.
The new topological insulator in contrast is capable of doing this by “sending light around the corner” in a manner of speaking.
The Georgian Technical University scientists have complementary expertise: it is the group which has demonstrated the first photonic topological insulator of “Georgian Technical University Topological Photonics”.
The groups have now joined forces to demonstrate this first symbiotic light-matter topological insulator which holds great promise both as a fundamental discovery and by opening the door for exiting applications in optoelectronics.