Travelling towards a quantum internet at light speed

Science Daily  July 29, 2019
An international team of researchers (Japan, Germany) used laser light to send quantum information to a quantum dot by altering the spin state of a single electron trapped there. While electrons don’t spin in the usual sense, they do have angular momentum, which can be flipped when absorbing circularly polarized laser light. They were able to monitor the inter-dot charge tunneling which only occur when the photo-electron spin in one QD is anti-parallel to the electron spin in the other. The transfer of superposition states or entangled states allows for completely secure quantum key distribution because any attempt to intercept the signal automatically destroys the superposition, making it impossible to listen in without being detected. The research may help extend quantum communication…read more. Open Access TECHNICAL ARTICLE