  The transition between massive Class II circumstellar disks and Class III
debris disks, with dust residuals, has not yet been clearly understood. Disks
are expected to dissipate with time, and dust clearing in the inner regions can
be the consequence of several mechanisms. Planetary formation is one of them
that will possibly open a gap inside the disk. According to recent models based
on photometric observations, T Cha is expected to present a large gap within
its disk, meaning that an inner dusty disk is supposed to have survived close
to the star. We investigate this scenario with new near-infrared
interferometric observations. We observed T Cha in the H and K bands using the
AMBER instrument at VLTI and used the MCFOST radiative transfer code to model
the SED of T Cha and the interferometric observations simultaneously and to
test the scenario of an inner dusty structure. We also used a toy model of a
binary to check that a companion close to the star can reproduce our
observations. The scenario of a close (few mas) companion cannot satisfactorily
reproduce the visibilities and SED, while a disk model with a large gap and an
inner ring producing the bulk of the emission (in H and K-bands) close to 0.1
AU is able to account for all the observations. With this study, the presence
of an optically thick inner dusty disk close to the star and dominating the H
and K- bands emission is confirmed. According to our model, the large gap
extends up to ~ 7.5 AU. This points toward a companion (located at several AU)
gap-opening scenario to explain the morphology of T Cha.
