Quantum Technologies
We are already surrounded by quantum technologies. From microprocessors, to digital cameras, to lasers—these technologies rely for their operation on the quantum behaviour of electrons in solids and on the stimulated emission of coherent radiation, respectively. Advances in experimental techniques and equipment over the past few decades have enabled the manipulation of single quantum objects (photons, atoms) to harness more advanced, subtle, aspects of quantum mechanics: superposition and entanglement. Thanks to these properties a new era of Quantum Technologies is now emerging, that promises: quantum sensors with higher sensitivity and accuracy; quantum secure communication; and, quantum computers capable of tackling complex physical problems inaccessible to classical computers.
Space is critical to the development and deployment of these new quantum technologies. Quantum sensors, by virtue of their heightened sensitivity, reach their maximum potential in the quiet environment afforded by space, far from gravitational fluctuations. Long-distance quantum secure communication on the ground is currently limited by optical fibre losses. Satellite quantum communication may establish quantum secure links across continents. The natural evolution of quantum computers and quantum communication will be the creation of quantum networks and, eventually, the Quantum Internet. It seems likely that satellite will play an important role as the global nodes of our future quantum connected world.