Topological insulators are semiconductors that are insulators on the inside
but conductors on the outside.
Using the magic of quantum "spin-orbit coupling" they were first theorised
in 2006 and actually demonstrated in 2008.
Now Jae-Hyuck Choi along with Mercedeh Khajavikhan and their colleagues
at the University of Southern California have developed the first electrically pumped room-temperature
topological laser.
They detailed their findings on June 8 2021 in the journal
Nature Communications.
These new lasers are claimed to more be efficient than conventional lasers
and could thus find use in optical communications, such as the Internet.
21 June 2011 backgrounder on Topological Insulators :-
https://spectrum.ieee.org/semiconduc...cal-insulators
The above article mentions :-
Quote:
Originally Posted by Joel E. Moore, IEEE
In fact, the ability of such a gas to be topologically complex is what led to these new materials. Until recently, electron gases had been found only at the junction of two semiconductors having different electronic properties. These gases are crucial for high electron mobility transistors (HEMTs), a form of field-effect transistor used in radar, imaging, and other applications that require high gain at high frequencies.
|
The super-fast High Electron Mobility Transistor (HEMT) which
uses quantum mechanical phenomena to work is of immense utility today.
There is one in every smartphone, satellite dish antenna, modern radar, DVD and
CD player in the world. My previous boss, who was an Australian
physicist working for Bell Labs in the US, happened to play a critical role
in their
invention.
6 July 2021 story on the Topological Laser :-
https://spectrum.ieee.org/tech-talk/...temp-topolaser
"Room temperature electrically pumped topological insulator lasers"
by Choi et. al. Nature Communications 8 June 2021 :-
https://www.nature.com/articles/s41467-021-23718-4