Physicists from Princeton University were the first in the world to create a device that allows a single electron to transfer its quantum state to a particle of light. Previously, such a process was impossible, since the quantum state of the electron was lost even before the transfer.
This device is the result of five years of research carried out in the HRL laboratory, owned by Boeing and General Motors. It is a semiconductor chip composed of layers of silicon and silicon-germanium alloy, widely used and cheap materials. The chip receives power from a network of nanowires, each of which is thinner than a human hair.
The energy allows the device to capture electrons between layers of silicon in structures known as quantum dots. Inside them, an electron can assume one of three possible states - 0, 1, or 0 and 1 at the same time, which is extremely important for the potential creation of quantum computers. After that, the electron can transfer its state to another electron, using a single photon as an intermediary.
Tests of the new device were successful, but now researchers from Princeton intend to go further. They want to improve their chip to give it the ability to control the spin of captured electrons. Free manipulation of the spins, or magnetic moments of electrons, will give scientists even greater control over the exchange of information between quantum bits.