The elusive quantum mechanical phenomenon called entanglement has now been made a reality in objects almost macroscopic in size. Results published in Nature show how two vibrating drumheads, the width of a human hair, can display the spooky action.
Novel quantum device design promises a regular flow of entangled electrons on demand
Quantum computer and many other quantum technologies rely on our ability to generate quantum entangled pairs of electrons. However, the systems developed so far typically produce a noisy and random flow of entangled electrons, which hinders synchronized operations on the entangled particles. Now, researchers from Aalto University in Finland propose a way to produce a regular flow of spin-entangled electrons.
Their solution is based on a dynamically driven Cooper pair splitter. In a Cooper pair splitter, two quantum dots near a superconductor are used to generate and separate a pair of entangled electrons known as a Cooper pair. When the Cooper pair splitter is driven with a static voltage, the result is a random and noisy process. A theoretical analysis by the Aalto team showed that driving the system dynamically with external gate voltages makes it possible to control the timing of the splitting process. As a result, exactly one pair of entangled electrons can be extracted during each splitting cycle, leading to a completely noiseless and regular flow of spin-entangled electrons. Such a device, which is feasible with current technology, would pave the way for dynamic quantum information processing with spin-entangled electrons, opening a broad range of possibilities for future quantum technologies.
The original research article, which was published 1.12.2021 in Physical Review Letters, can be accessed here: Dynamic Cooper Pair Splitter