Entanglement dynamics of two Ising-coupled qubits with non-perpendicular local driving fields

摘要

We present an approximate analytical solution to the dynamic equation of twoIsing-coupled qubits with oscillating classical control fields that arenon-perpendicular to the static drift fields. This is a situation that hasrecently arisen in some solid-state experiments. With our solution we derivethe analytical expressions for the local invariants as well as the localrotations needed to isolate a purely nonlocal gate. This determines the set ofparameters that are required to generate any entangling gate. Moreover, we useour results to describe a recent experimental work on capacitively coupledsinglet-triplet qubits in GaAs and discuss possible differences for a similardevice in silicon.