  We report on the study of a detection scheme based on a Bloch separator in
two-photon Bragg interferometers. We increase the spatial separation between
the two output ports of the interferometer by selectively imparting 30 Bloch
oscillations to one of them before their detection via time of flight. This
method allows increasing the duration of the interferometer by reducing the
time for discriminating the ports of the interferometer at detection. We study
in detail the impact of this separator on the performance of a dual gravity
sensor, and in particular on its measurement sensitivities to gravity
acceleration and gravity gradients.
