The reporter learned from the University of science and technology of China on the 5th that pan Jianwei and his colleagues have made important experimental progress in long-distance quantum state transmission by using the "Mozi" Quantum Science Experimental Satellite: the long-distance quantum state transmission between two ground stations 1200 kilometers away on the earth has been realized for the first time**
It is reported that the distance of thousands of kilometers is a new record of surface quantum state transmission, and an important step towards building a global quantum information processing and quantum communication network.
Relevant research results were recently published online in the internationally renowned academic journal Physical Review Letters.
Long distance quantum state transmission is one of the important ways to construct quantum communication network, and it is also a necessary element to realize a variety of quantum information processing tasks. With the aid of long-distance quantum entanglement distribution, quantum states can complete long-distance transmission by measuring and then reconstructing, and the transmission distance can be infinity in theory. However, in the implementation, the distance and quality of quantum entanglement distribution will be affected by channel loss, decoherence and other factors. How to break through the limitation of transmission distance has always been one of the important research objectives in this field.
Using spaceborne entanglement source to distribute entanglement to distant places, and then prepare and reconstruct quantum states is one of the most possible paths to realize long-distance quantum state transmission. However, due to the influence of atmospheric turbulence, it is very difficult to realize quantum state measurement based on quantum interference after photons propagate in atmospheric channel.
In 2016, with the successful launch of the world's first quantum science experiment satellite "Mozi", the "Mozi" platform provided valuable entanglement distribution resources for quantum communication experiments. In order to overcome the problem of quantum light interference after long-distance turbulent atmospheric transmission, the experimental team completed the transmission verification of long-distance quantum states between Yunnan Lijiang station and Delingha ground station 1200 kilometers away by using optical integrated bonding technology and quantum teleportation scheme.
This work lays an important foundation for building a global quantum information processing network in the future.