Congratulation to Mirko Rocci and co-Authors for their recent publication on NanoLetters !
In this paper they demonstrate tunable bistability and a strong negative differential resistance in InAs/GaSb core–shell nanowire devices embedding a radial broken-gap heterojunction. Nanostructures have been grown using a catalyst-free synthesis on a Si substrate. Current–voltage characteristics display a top peak-to-valley ratio of 4.8 at 4.2 K and 2.2 at room temperature. The Esaki effect can be modulated—or even completely quenched—by field effect, by controlling the band bending profile along the azimuthal angle of the radial heterostructure. Hysteretic behavior is also observed in the presence of a suitable resistive load. Their results indicate that high-quality broken-gap devices can be obtained using Au-free growth.