Atomically thin transition metal dichalcogenides have emerged aspromising candidates for sensitive photodetection. Here, we report a photoconductivity study of biased mono-and bilayer molybdenum disulphide fieldeffect transistors. We identify photovoltaic and photoconductive effects, which both show strong photogain. The photovoltaic effect is described as a shift in transistor threshold voltage due to charge transfer from the channel to nearby molecules, In our work, we investigated back-gated FETs 27-29 ( Figure 1a) with monolayer and bilayer MoS 2 channels. The devices were fabricated by mechanical exfoliation of 3 natural MoS 2 (SPI Supplies) onto a Si/SiO 2 wafer with ! !" = 280 nm oxide thickness.Standard photolithographic and metal evaporation techniques were employed to produce the drain and source contact electrodes (5 nm Ti, 50 nm Au). Table S1

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Future wearable electronics, displays and photovoltaic devices require materials which are mechanically flexible, lightweight and low-cost, in addition to being electrically conductive and optically transparent [1][2][3]. Nowadays indium tin oxide (ITO) is the most wide spread

The advent of microcomputers in the 1970s has dramatically changed our society. Since then, microprocessors have been made almost exclusively from silicon, but the ever-increasing demand for higher integration density and speed, lower power consumption and better integrability with everyday goods has prompted the search for alternatives. Germanium and III–V compound semiconductors are being considered promising candidates for future high-performance processor generations and chips based on thin-film plastic technology or carbon nanotubes could allow for embedding electronic intelligence into arbitrary objects for the Internet-of-Things. Here, we present a 1-bit implementation of a microprocessor using a two-dimensional semiconductor—molybdenum disulfide. The device can execute user-defined programs stored in an external memory, perform logical operations and communicate with its periphery. Our 1-bit design is readily scalable to multi-bit data. The device consists of 115 transistors and constitutes the most complex circuitry so far made from a two-dimensional material.

Strain engineering is widely used in material science to tune the (opto-)electronic properties of materials and enhance the performance of devices. Two-dimensional atomic crystals are a versatile playground to study the influence of strain, as they can sustain very large deformations without breaking. Various optical techniques have been employed to probe strain in two-dimensional materials, including micro-Raman and photoluminescence spectroscopy. Here we demonstrate that optical second harmonic generation constitutes an even more powerful technique, as it allows extraction of the full strain tensor with a spatial resolution below the optical diffraction limit. Our method is based on the strain-induced modification of the nonlinear susceptibility tensor due to a photoelastic effect. Using a two-point bending technique, we determine the photoelastic tensor elements of molybdenum disulfide. Once identified, these parameters allow us to spatially image the two-dimensional strain field in an inhomogeneously strained sample.