Quantum teleportation, as the name suggests, is the process wherein the information on the state of a quantum system can be transmitted between two locations. This requires the help of traditional communication methods and the previously shared quantum entanglement between the sending and receiving spots. In 2017, the Chinese did something that broke new ground — they teleported certain properties of photons from Earth to space.
“To pull it off, the researchers used a special transmitter called Ngari, which sits on a Tibetan mountain range… To entangle photons, researchers beamed an ultraviolet laser through a special crystal. The crystal created pairs of photons with the opposite — yet unknown — states of polarization. (Polarization is the same property of light that polarized sunglasses can filter out to improve contrast.) In doing so, they created objects called qubits, or quantum-entangled bits,” according to Business Insider.
The laser beam and the pairs of quantum entangled photons were then split up using mirrors. One photon was retained on the ground while the other was sent to the satellite Micius at around 4,080 entangled photons per second. The satellite was about 870 miles (1,400 kilometers) in space when the experiment was carried out. The experiment broke all existing records when it came to the distance of quantum teleportation. And it was the first time that quantum teleportation was used to send something into space.
The study was critical in demonstrating that China was now becoming a leader in cutting edge technologies. The results laid the possibility of the eventual creation of a quantum Internet that would be far more powerful than what we use now. Such an Internet would be so secure that no one could eavesdrop on the network without the administrator knowing about it. How fast will quantum Internet be? To put it into perspective — you will be able to download an entire season of your favorite Netflix show in just 10 seconds rather than having to wait several hours.
Another breakthrough in quantum teleportation was achieved recently by Chinese researchers in association with scientists from Austria. They succeeded in teleporting 3-dimensional quantum states for the first time in history. The study can contribute to the development of quantum computers. In their experiment, the researchers’ teleported a photon’s quantum state to another distant photon.
“Previously, only two-level states (‘qubits’) had been transmitted, i.e., information with values ‘0’ or ‘1.’ However [this time], the scientists succeeded in teleporting a three-level state, a so-called ‘qutrit.’ In quantum physics, unlike in classical computer science, ‘0’ and ‘1’ are not an ‘either/or’ — both simultaneously, or anything in between, is also possible. The Austrian-Chinese team has now demonstrated this in practice with a third possibility ‘2,’” according to Phys.Org.
Higher-dimensional quantum systems are capable of transmitting far greater information than qubits. As such, the research paves the way for a quantum Internet that will be able to move massive quantities of data at high speeds. Though the current study only dealt with the transmission of 3-dimensional quantum states, it can theoretically extend to many more dimensions. The researchers now wish to focus on transmitting the entire quantum state of a single photon or atom. The study was conducted by the University of Science and Technology in China together with the Austrian Academy of Sciences and the University of Vienna.