High-performance molybdenum disulfide field-effect transistors with spin tunnel contacts.

Molybdenum disulfide has recently emerged as a promising two-dimensional semiconducting material for nanoelectronic, optoelectronic, and spintronic applications. Here, we investigate the field-effect transistor behavior of MoS2 with ferromagnetic contacts to explore its potential for spintronics. In such devices, we elucidate that the presence of a large Schottky barrier resistance at the MoS2/ferromagnet interface is a major obstacle for the electrical spin injection and detection. We circumvent this problem by a reduction in the Schottky barrier height with the introduction of a thin TiO2 tunnel barrier between the ferromagnet and MoS2. This results in an enhancement of the transistor on-state current by 2 orders of magnitude and an increment in the field-effect mobility by a factor of 6. Our magnetoresistance calculation reveals that such integration of ferromagnetic tunnel contacts opens up the possibilities for MoS2-based spintronic devices.

Enhancing the molecular signature in molecule-nanoparticle networks via inelastic cotunneling.

Charge transport in networks of nanoparticles linked by molecular spacers is investigated. Remarkably, in the regime where cotunneling dominates, the molecular signature of a device is strongly enhanced. We demonstrate that the resistance ratio of identical networks with different molecular spacers increases dramatically, from an initial value of 50 up to 10(5) , upon entering the cotunneling regime. Our work shows that intrinsic molecular properties can be amplified through nanoscale engineering.