Bringing Plasmonics to Semiconductors
Electronics have dominated technology for decades but this reign may soon end as the coming technologies of spintronics, plasmonics, and quantum computers are developed. Of course, some of these technologies can be integrated with electronics, to give us the best of both worlds. Published in the Optical Society of America’s Optical Materials Express journal is research that will greatly aid in bringing plasmonics to modern semiconductor technology.
Plasmonics use quasiparticles called plasmons in a similar way to how electronics use electrons. Plasmons are actually an electron and photon coupled together with new properties. For example, a photon cannot be any smaller than half of its wavelength, but when in a plasmon, it can be 100 times smaller. This allows an optical signal to travel along nanoscale paths, like electrons do, but requires far less energy to do so reliably.
To create a plasmon, researchers have to shine a laser onto a piece of metal, and normally they use gold or silver, with silver being the best choice. Unfortunately, neither of these materials interacts well with semiconductors, so plasmonics-electronic hybrid technologies are not a possibility using them. The research in the journal though discusses using titanium nitride, a ceramic material, for the creation of plasmons. This material is already used in electronics as a barrier, so it will play nice with semiconductors, unlike the metals.
Of course if the material is not very good at producing plasmons or transmitting them, then this would be useless. This is not the case though. The researchers find titanium nitride has as strong of plasmonics capabilities as gold, with silver still in the lead. However, only pure silver is superior, and pure silver films are easily degraded in the air, making them less potent.
This is a very important discovery for the future of plasmonics, as it may bring them to the world much sooner. Titanium nitride may also prove useful in the creation of metamaterials too, which also take advantage of plasmons. Pure silver would still be the choice for invisibility cloaks, but metamaterials can do more than just hide things.