Have researchers developed the fastest ever semiconductor?
Columbia University chemists say they have discovered the world's fastest and most efficient semiconductor – a superatomic material called Re6Se8Cl2.
Writing last month in Science, the team explained how the atomic structure of conventional semiconductors is subject to vibrations, resulting in the generation of particles known as phonons. These phonons lead to scattering, which dissipates energy as heat and slows down information transfer.
The researchers decided instead to test the transport of energy through superatoms – clusters of atoms bound together to behave like one big atom. They synthesized a superatomic semiconductor called Re6Se8Cl2 which, in principle, shouldn’t have conducted much at all.
In fact, “it was the fastest thing we’ve ever seen.”
Experiments showed why. The excitons in Re6Se8Cl2 would bind with phonons to create new quasiparticles called acoustic exciton-polarons. These particles move twice as fast as electrons in silicon.
“This is the only material that anyone has seen sustained room-temperature ballistic exciton transport in. But we can now start to predict what other materials might be capable of this behavior that we just haven’t considered before,” said Columbia chemistry professor Milan Delor. “There is a whole family of superatomic and other 2D semiconductor materials out there with properties favorable for acoustic polaron formation.”
