Single molecule led is ‘world’s first’

The device is formed from a single polythiophene wire made of hydrogen, carbon and sulphur, which was placed between the tip of a scanning tunneling microscope and a gold surface. The scientists recorded the light emitted when a current passed through the nanowire and observed that light was only emitted when electrons went from the tip of the microscope towards the gold surface. When the polarity was reversed, light emission was negligible. This experimental tour de force sheds light on the interactions between electrons and photons at the smallest scales (for every 100,000 electrons injected into the thiophene wire, a photon was emitted). Moreover, the researchers believe it represents yet another step towards creating components for a molecular computer in the future.