  Quantum discrimination and estimation are pivotal for many quantum
technologies, and their performance depends on the optimal choice of probe
state and measurement. Here we show that their performance can be further
improved by suitably tailoring the pulses that make up the interferometer.
Developing an optimal control framework and applying it to the discrimination
and estimation of a magnetic field in the presence of noise, we find an
increase in the overall achievable state distinguishability. Moreover, the
maximum distinguishability can be stabilized for times that are more than an
order of magnitude longer than the decoherence time.
