Environment and technology
The promises of quantum technologies Based on the unusual behaviour of microscopic quantum objects, new technology aims to bring radical computing capacity and bulletproof encryption.
Secure messaging Quantum encryption has been implemented many times using optical fibres over distances greater than 100 km. In August 2016 China placed equipment into orbit to test satellite-based quantum cryptography.
Journalist: Daniel Saraga Infographics: onlab, Thibaud Tissot
Gravitation Based on the wave nature of atoms, atom interferometers can detect minute changes in the gravitational field, which can be useful as gyroscopes for inertial navigation (e.g., for submarines) or in geological surveys for mineral or oil.
ntum Qua Secure Timekeeping Clocks built on entangled qubits are already more accurate than the usual atomic clocks used in GPS satellites, and better for defining the official duration of a second.
A timeline for new technologies
The d
li m
etec
tion
Quantu m se
it
nsi ng
Microscopy A new imaging device using entangled photons could improve microscopy in low light.
Magnetic sensor A crystal defect found in diamonds acts as an isolated artificial atom sensitive to extremely weak magnetic fields, useful for medical imaging or oil exploration. This sensor would replace SQID, an existing quantum technology based on superconducting materials but only functional at –170° C.
Quantum sensing The wave nature of quantum matter is extremely delicate and sensitive to its environment. Measuring how fast it decays (the decoherence) allows it to detect and quantify incredibly weak signals. Quantum communication Entangled photons (light particles) can be used for encryption. A sender and a receiver create and instantaneously share a random succession of bits (011011101011 …), which acts as a secret key to encode a message. The latter is sent by conventional means, but only the receiver can decode it, as only she holds the key.
44
ent
P re s
d e ca d N ex t
Long
te r m
es
Quantum computers Information stored as quantum bits (qubits) is very fragile, but quantum entanglement and parallelism in principle allow us to solve certain problems far quicker than with usual computers.