  Following a recent discovery of the Insulator-to-Metal Transition induced by
electric field in GaTa$_{4}$Se$_{8}$, we performed a detailed Scanning
Tunneling Microscopy/Spectroscopy study of both pristine (insulating) and
transited (conducting) crystals of this narrow gap Mott insulator. The
spectroscopic maps show that pristine samples are spatially homogeneous
insulators while the transited samples reveal at nanometer scale a complex
electronic pattern that consists of metallic and super-insulating patches
immersed in the pristine insulating matrix. Surprisingly, both kinds of patches
are accompanied by a strong local topographic inflation, thus evidencing for a
strong electron-lattice coupling involved in this metal-insulator transition.
Finally, using a strong electric field generated across the STM tunneling
junction, we demonstrate the possibility to trig the metal-insulator transition
locally even at room temperature.
