QuantumFuture is an intrinsically multidisciplinary project, covering different, but strongly correlated and complementary research fields.
State of the art.
Quantum key distribution (QKD) represents an innovative protocol for key distribution: a QKD system is a telecommunication system that can create a perfectly secure symmetric key at the transmitter and at the receiver.
Random numbers are used continuously in countless applications: all cryptographic protocols need random numbers to encrypt digital and analogical communications.
Random numbers are used for simulations to understand how complex systems work: from cellular reproductive mechanisms, to the interactions of sub-nuclear particles, passing by financial trends.
When the free space channel is used either for conventional and quantum communications, the propagation of the beam through the atmosphere can cause degradation of the wavefront and hence decrease the performance of the system. In this perspective the use of deformable optical component is the most promising way in order to overcome these limitation.
This field, known as Adaptive Optics and born for astronomical applications, would be one of the key point when dealing with single photons applications that exploit the free space channel both for ground and space link. Adaptive Optics can be indeed exploited also for general optimization of optical problems by acting on the wavefront as soon as an optimal condition is required.
The theoretical advantages provided by the quantum information paradigm are nowadays well established, and many diverse solid-state, optical, superconductor candidates for scalable quantum devices are being tested, as well as different approaches to the computation paradigm.
Encoding information in quantum systems and sending it through a communication channel permits to improve state-of-the-art classical protocols in the reception, and the security of the signal. At the transmitter, we can place a laser source that produces a train of quantum states, and we can modulate the phase of these pulses performing the so called Phase Shift Keying (PSK) modulation. It has been shown that the error probability of an optical transmission system encoding information in quantum states can significantly improve the performance with respect to the analogue classical optical transmission.
Starting from the experience of our Matera experiment we study the atmosphere propagating channel as it will be the only medium where our quantum bits or optical coherent pulse will travel. We will be able to overcome the losses and noise introduce by the atmosphere with particular attention to the problem of maintaining the coherence property, augmenting the spatial pointing and improving the performances of all our different experiments assuring a good wavefront in the receiving telescopes.