Electrical and Mechanical Properties of Atomically Thin Layers of MoS2

Two-dimensional crystals are promising materials for next-generation flexible electronic devices. Although graphene is by far the most studied two-dimensional crystal, its lack of a bandgap hampers its application in semiconducting and photonic devices. A large bandgap is a requirement, for instance, to fabricate field-effect transistors with a large current on/off ratio and low power consumption. In contrast to graphene atomically thin MoS2 crystals show a large intrinsic bandgap making it a potentially interesting material for electronic devices and sensors. In this talk I will present our recent results on the mechanical and electrical properties of this material. In particular, we have studied the elastic properties of MoS2 in freely suspended nanosheets, with thicknesses ranging from 5 to 25 layers using atomic force microscopy [1] and the electrostatic screening by single and few-layer MoS2 sheets by means of electrostatic force microscopy [2]. References [1] Andres Castellanos-Gomez, Menno Poot, Gary A. Steele, Herre S. J. van der Zant, Nicolás Agraït, and Gabino Rubio-Bollinger, Elastic Properties of Freely Suspended MoS2 Nanosheets, Adv. Mater. 24, (2012) 772–775. [2] Andres Castellanos-Gomez, Emmanuele Cappelluti, Rafael Roldán, Nicolás Agraït, Francisco Guinea and Gabino Rubio-Bollinger, Electric field screening in atomically thin layers of MoS2: the role of interlayer coupling, Adv. Mater. 25, (2013) 899–903.