Context

• Recently, satellite Micius has sent light particles to Earth to establish the world’s most secure communication link. 

About Micius

• It is the world’s first quantum communications satellite,launched by China in 2016.
• The satellite serves as the source of pairs of entangled photons.
• Entangled photons are twinned light particles whose properties remain intertwined no matter how far apart they are.
• If one of the photons is manipulated, the other will be similarly affected at the very same moment
• It is this property that lies in the heart of the most secure forms of quantum cryptography(the study of concepts like encryption and decryption).
• If one of the entangled particles is used to create a key for encoding messages, only the person with the other particle can decode them.