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Researchers using the phenomenon that backs St. Paul's Cathedral in London where a whisper is audible from the other side of the dome, have created an optical device that might lead to new and more powerful computers. The developed components of these computers would reportedly run on light.

Researchers created an optical diode by coupling tiny optical resonators - one with gain and another with loss- on a silicon chip. 

"This diode is capable of completely eliminating light transmission in one direction and greatly enhancing light transmission in the other nonreciprocal light transmission," says Bo Peng, a graduate student and the paper's lead author, in the press release.

Theoretically, an electrical diode prevents electricity from back flow along a wire providing protection to important parts of an electronic circuit or processor. An optical diode also has the identical function with light.

"We believe that our discovery will benefit many other fields involving electronics, acoustics, plasmonics and meta-materials," said Lan Yang, PhD, associate professor of electrical and systems engineering, in the press release. 

"Coupling of so-called loss and gain devices using PT (parity-time)-symmetry could enable such advances as cloaking devices, stronger lasers that need less input power, and perhaps detectors that could 'see' a single atom."

Simplifying the process, researchers explained when a 'lossy' system is coupled with 'gain' system such that loss of energy exactly equals gain at an equilibrium point, 'phase transition' occurs.

"More broadly, our paper shows how a concept with its roots in mathematical physics can be utilized to provide solutions to practical problems, opening new possibilities for controlling and manipulating light on-chip," the team said. 

"PT-symmetry breaking alone is not sufficient to have nonreciprocal response; operation in the nonlinear regime is also necessary. In the linear regime, light transmission is always reciprocal regardless of whether PT-symmetry is broken or not."

The findings of the study have been published in the journal Nature Physics.