Scientists Create, Store, and Retrieve Quantum Data for the First Time

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Scientists from various European universities managed to store and retrieve data from quantum computers for the first time in history- an essential step in quantum networking as the world gears up for the next generation of computing.

While current quantum computers are already way ahead of their classical counterparts and are getting increasingly better, if scientists cannot reliably transmit quantum data over a network, all these advances could mean nothing. One issue with quantum data is its tendency to get lost when transmitted over long distances due to its nature, and so scientists have been looking for ways to divide the network into smaller segments and link them up to share the same quantum state.

Current internet networks experience a similar issue, for which we use amplifiers that read and amplify the signal so that it remains intact over long distances. However, this method doesn’t work with quantum data since any attempt to read or copy it would destroy it – this is why quantum information has to be stored and retrieved throughout the network to transmit data over long distances, requiring a quantum memory device.

According to Interesting Engineering, one approach to sharing quantum information is using entangled photons (because the particles are entangled and cannot be understood individually) but sharing the entangled photons over long distances requires several devices to create, store, and retrieve them over the transmission network. Scientists tried creating such devices but found it extremely difficult to generate entangled photons on demand and develop a compatible quantum memory to store them. This is mainly because the devices use different wavelengths, so they struggle with interfacing.

Scientists from the Imperial College, the University of Southampton, the University of Stuttgart, and the University of Wurzburg collaborated to solve this issue by developing a device that uses the same wavelength. This device generated non-entangled photons (also called quantum dots), which were passed through a quantum memory system that stored them with the help of rubidium atoms. They then used a laser to turn the memory on and off and release the photons on demand.

Even more importantly, the wavelength used by the device is compatible with the fiber optic infrastructure that is currently used to connect the world, making it easier to deploy when quantum computers are ready for mass use.

The scientists report that their next steps would be to improve the system by reducing its size and increasing the duration of photon storage.