In the world of quantum mechanics, theoretical physicists have the long-held belief that quantum teleportation is possible but it needs particles that must be entangled. However, a group of scientists recently achieved this without using entanglement.
Teleportation is a type of quantum communication which requires two particles that are inextricably linked that they affect each other no matter how far their distance is from each other. Entanglement happens when another particle, such as photons, travel between the two particles.
However, there’s a type of quantum communication called direct counterfactual quantum communication that does not require entanglement because it uses a phenomenon called quantum Zeno effect.
Explaining the Quantum Zeno Effect
The quantum Zeno effect happens when an unstable quantum system is measured. In the world of quantum mechanics, systems always change when it is measured. In such case, an unstable system never decays even when they are measured. Therefore, the quantum Zeno effect produces a system that is effectively frozen with very high probability.
Counterfactual quantum communication is based on this phenomenon where a quantum state transfers from one place to another without using any particle between them.
This is the system used by researchers from the University of Science and Technology of China. They built two single-photon detectors in the output ports in an array of beam splitters. Using the Zeno effect, it is possible for them to detect when the photons pass through.
The system worked because they embedded the messages in the light which functions as a wave rather than particles in the quantum world. Thus, they were able to transmit messages without actually sending particles.
Impact In Quantum Mechanics
The researchers said that the study has a significant effect on the future of quantum mechanics. One of these uses is in the area of creating images for ancient artifacts which can’t have sunlight shine directly on them.
The research will be checked by independent researchers to make sure that counterfactual quantum communication was indeed achieved.
The study was published in the Proceedings of the National Academy of Sciences.
Source : By Chris Brandt, University Herald