In what could be a breakthrough discovery in transfer of quantum information, scientists at the Cavendish Laboratory of Cambridge University have used sound waves to control the movement of electrons.
Generally, electrons move along a wire in a zigzag manner. Such a movement can lead the electrons to forget their path or more technically, there is a loss of coherence in its quantum state.
In this study, scientists discovered that one electron can be captured in a quantum dot located along the internal surface of Gallium Arsenide piece. They then created an empty channel consisting of higher energy levels than the surrounding electrons and set it up at a distance of .4 µm. The scientists sent a sound wave for a nanosecond along the surface past the quantum dot. The electrical wave created by the sound wave carried the electron through the channel to reach the quantum dot on the other side of the channel. Another sound wave was then created to make the electron return to its starting point in the same manner. The study team was able to achieve 60 such rallies. The back-and-forth movement of the of the electron is similar to that of a ping-pong ball.
However, the team has not been able to establish if the electrons retain their quantum state after the movements. According to Chris Ford, leader of the research team from the lab’s Semiconductor Physics Group, this method could be used to move quantum bits of information along a quantum circuit to complete a quantum computer.
Source: http://www.cam.ac.uk/