Photo by: Cirilo Cortez via Wikipedia
One year ago, the world’s first quantum satellite was launched by Chinese physicists. The 1,400-pound entity is designed to send and receive bits of information, which is encoded in photons of infrared light instead of the typical radio wave transmission.
This brand new technology is called quantum communications. Field experts say this can be much more secure than any existing info relay system.
The group of physicists who launched the massive satellite has published several papers over the summer in Science and Nature. According to the papers, they sent entangled photons between Micius (the name of the satellite) and several ground stations. The name, Micius, was derived from the name of an ancient Chinese philosopher (alternately named Mozi) who discussed optics in his writings.
Think of quantum communications in terms of mailing a letter; entangled photons would be the envelope. The entangled photons basically keep the message secure.
Leading researcher on the Micius project, Jian-Wei Pan of the University of Science and Technology of China, has said that he wants to launch more quantum satellites in the next five years. Pan hopes that quantum communications will span multiple countries by 2030. In 13 years, you can expect quantum internet he says.
Quantum internet means there will be multiple parties basically pinging information back and forth in the form of quantum signals; however, the experts have yet to figure out the details of such an endeavor.
Thomas Jennewin, a physicist at the University of Waterloo, says, “'Quantum internet' is a vague term.” He added, “People, including myself, like to use it. However, there’s no real definition of what it means.”
The reason for the vagueness is the fact that this technology is in its nascent stage, and physicists still cannot control and manipulate quantum signals very well.
Pan’s satellite can send and receive signals well enough , but it does not have the ability to store information yet. The top quantum memories can only store information for under an hour, while researchers still haven't figured out what type of material could make up the best quantum memory.
Physicists also haven't found a way to efficiently transmit these signals between the nodes and the future quantum web, as of yet.
To cover the earth with quantum satellites would be extremely expensive. The cost of Micius was $100 million.
Optical fiber ground-based transmission has its problems too, with signals dying after transmitting around 60 miles. A snag in this is that those signals cannot be amplified, which is prompting researchers to develop quantum repeaters for transmitting signals across long distances.
All of this research is expected to take many years.
However, researchers worldwide are in the process of developing a chip which may enable a classic computer to connect with a quantum network. The idea is that people could use classic computer methods the majority of the time, and simply hook up with the quantum network for certain streamlined tasks.