The record-breaking transfer has been achieved at the U.S. Department of Energy’s Oak Ridge National Laboratory. Superdense coding is a technique used to send two bits of classical information using only one qubit (a unit of quantum information). With the coding processes the types of particles used to process information include photons, protons and electrons.
In setting the record, the research group transferred 1.67 bits per qubit along a fiber optic cable. This broke the previous record of 1.63 per qubit.
As to what this means in practice, the new record relates to quantum computing. Quantum computing studies theoretical computation systems. While research remains at an early stage, large-scale quantum computers would theoretically be able to solve certain problems much quicker than any classical computers.
With a conventional computer, such devices transmit information in the form of bits (in the binary coding of a 1 or a 0). With quantum computing, qubits are used. These use two states simultaneously and can represent more information than a bit. Key to the development of quantum computers is information transfer, which is why the attempt was made to accelerate the transfer of qubits.
By using a common fiber optic cable together with standard photon detectors, the researchers have brought the qubit transfer a step closer to practical use. With the new study, this was undertaken within a laboratory. Here the official Oak Ridge National Laboratory logo was sent between two end points.
The finding will help in the path towards developing quantum computing and finding cost-effective means to condense and transfer information very rapidly. In a research note, the lead scientist Brian Williams said that the “experiment demonstrates how quantum communication techniques can be integrated with conventional networking technology.”
The research has been published in the journal Physical Review Letters, in a paper called “Superdense Coding over Optical Fiber Links with Complete Bell-State Measurements.”
