4 papers · 1 filter
A Quantum Field Theory Twist to Photon Angular Momentum
G. F. Calvo, A. Picon, E. Bagan
A quantum field theory approach is put forward to generalize the concept of classical spatial light beams carrying orbital angular momentum to the single-photon level. This quantiz…
Aligning Spatial Frames Through Quantum Channels
E. Bagan, R. Munoz-Tapia
We review the optimal protocols for aligning spatial frames using quantum systems. The communication problem addressed here concerns a type of information that cannot be digitalize…
Optimal reconstruction of a pure qubit state with local measurements
E. Bagan, M. Baig, A. Monras +1
We analyse the reconstruction of an unknown pure qubit state. We derive the optimal guess that can be inferred from any set of measurements on N identical copies of the system with…
Communicating a direction using spin states
E. Bagan, M. Baig, R. Munoz-Tapia
The communication of directions using quantum states is a useful laboratory test for some basic facts of quantum information. For a system of spin-1/2 particles there are different…