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arXiv · 1709.03537

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

F. A. Calderon-Vargas·J. P. Kestner
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Abstract

We present an approximate analytical solution to the dynamic equation of two Ising-coupled qubits with oscillating classical control fields that are nonperpendicular to the static drift fields. This is a situation that has recently arisen in some solid-state experiments. With our solution we derive the analytical expressions for the local invariants as well as the local rotations needed to isolate a purely nonlocal gate. This determines the set of parameters that are required to generate any entangling gate. Moreover, we use our results to describe a recent experimental work on capacitively coupled singlet-triplet qubits in GaAs and discuss possible differences for a similar device in silicon.

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F. A. Calderon-Vargas, J. P. Kestner. 2018-04-10. Entanglement dynamics of two Ising-coupled qubits with nonperpendicular local driving fields. https://doi.org/10.1103/physrevb.97.125311

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