  In this paper, we address the adiabatic technique for quantum estimation of
the azimuthal orientation of a magnetic field. Exactly solving a model
consisting of a two-qubit system, where one of which is driven by a static
magnetic field while the other is coupled with the magnetic field rotating
adiabatically, we obtain the analytical expression of the quantum Fisher
information (QFI). We investigate how the two-qubit system can be used to probe
the azimuthal direction of the field and analyze the roles of the intensities
of the magnetic fields, Dzyaloshinskii-Moriya interaction, spin-spin coupling
coefficient, and the polar orientation of the rotating field on the precision
of the estimation. In particular, it is illustrated that the QFI trapping or
saturation may occur if the qubit is subjected to a strong rotating field.
Moreover, we discuss how the azimuthal direction of the rotating field can be
estimated using only the qubit not affected by that field and investigate the
conditions under which this strategy is more efficient than use of the qubit
locally interacting with the adiabatically rotating field. Interestingly, in
the one-qubit scenario, it was found that when the rotating field is weak, the
best estimation is achieved by subjecting the probe to a static magnetic field.
