  A nanodiamond with an embedded nitrogen-vacancy (NV) center is one of the
experimental systems that can be coherently manipulated within current
technologies. Entanglement between NV center electron spin and mechanical
rotation of the nanodiamond plays a fundamental role in building a quantum
network connecting these microscopic and mesoscopic degrees of motions. Here we
present a protocol to asymptotically prepare a highly entangled state of the
total quantum angular momentum and electron spin by adiabatically boosting the
external magnetic field.
