Collapse and revival and cat states with an N -spin system
Shane Dooley, Francis McCrossan, Derek Harland, M. J. Everitt, Timothy P. Spiller · Physical Review A · 2013
We discuss collapse and revival of Rabi oscillations in a system comprising a qubit and a ``big spin'' (made of $N$ qubits, or spin-$1/2$ particles). We demonstrate a regime of behavior analogous to conventional collapse and revival for a qubit-field system, employing spin coherent states for the initial state of the big spin. These dynamics can be used to create a cat state of the big spin. Even for relatively small values of $N$, states with significant potential for quantum metrology applications can result, giving sensitivity approaching the Heisenberg limit.