How current is conducted in semiconductors made of nanocrystals

Researchers at ETH have provided the first theoretical explanation for how electrical current is conducted in semiconductors made of nanocrystals. In the future, this could lead to the development of new sensors, lasers or LEDs for TV screens.

A few years ago, we were introduced to TV screens featuring QLED technology that produces brilliant colours. The “Q” here stands for “quantum dot”. Quantum dots are crystals of a semiconductor material only a few nanometres in size that consist of a couple of thousand atoms. Those nanocrystals are so tiny that the electrons in them can only take on certain well-defined quantum mechanical energy levels. As a consequence, when quantum dots are illuminated by the backlight of a TV, light of a particular colour is emitted by quantum jumps between those levels.

In next generation QLED TVs, the hope is to use electricity to make the quantum dots glow on their own instead of needing a backlight. Up to now, however, the theoretical understanding of how electrical current moves through a thin film of nanocrystals was lacking. A team of researchers from the Department for Information Technology and Electrical Engineering of ETH Zurich led by Vanessa Wood have now closed that gap, as they report in the scientific journal Nature Communications.

Read more.

Source: “A new theory for Semiconductors made of nanocrystals”, Oliver Morsch, ETH Zurich News