Konstantinos Anastasiou

University of Exeter | UoE · Department of Physics and Astronomy

The electrical behavior and the photoresponse of rhenium disulfide field-effect transistors (FETs) have been widely studied; however, only a few works have investigated the photocurrent as a function of temperature. In this paper, we perform the electrical characterization of few-layer ReS2-based FETs with Cr–Au contacts over a wide temperature ran...

Ballistic graphene p-n junctions are uniquely suited to develop electrical counterparts of optical circuits as the large transparency enables a better carrier modulation in their interfaces than the diffusive junctions. Here we demonstrate a low-cost and scalable method for the fabrication of ballistic planar graphene p-n junctions based on the dep...

Abstract This study reports the optoelectronic characterization of few‐layer ReSe2field effect transistors at different pressures. The output curves reveal dominant n‐type behavior and a low Schottky barrier at the metal contacts. The transfer curves show a significant hysteresis that can be exploited in memory devices with an order ofmagnitude mem...

Tuning the charge transport properties of two-dimensional transition metal dichalcogenides (TMDs) is pivotal to their future device integration in post-silicon technologies. To date, co-doping of TMDs during growth still proves to be challenging, and the synthesis of doped WSe2, an otherwise ambipolar material, has been mainly limited to p-doping....

We report the fabrication and optoelectronic characterization of field-effect transistors (FETs) based on few-layer ReSe2. The devices show n-type conduction due to the Cr contacts that form low Schottky barriers with the ReSe2 nanosheet. We show that the optoelectronic performance of these FETs is strongly affected by air pressure, and it undergoe...

The Hubble Space Telescope (HST) has obtained multi-epoch observations providing the opportunity for a comprehensive variability search aiming to uncover new variables. We have therefore undertaken the task of creating a catalog of variable sources based on version 3 of the Hubble Source Catalog (HSC), which relies on publicly available images obta...

Aims.Over its lifetime and despite not being a survey telescope, theHubble Space Telescope (HST)has obtained multi-epoch observations by multiple, diverse observing programs, providing the opportunity for a comprehensive variability search aiming to uncover new variables. We have therefore undertaken the task of creating a catalog of variable sourc...

Similar to silicon-based semiconductor devices, van der Waals heterostructures require integration with high- k oxides. Here, we demonstrate a method to embed and pattern a multifunctional few-nanometer-thick high- k oxide within various van der Waals devices without degrading the properties of the neighboring two-dimensional materials. This transf...

Like silicon-based semiconductor devices, van der Waals heterostructures will require integration with high-K oxides. This is needed to achieve suitable voltage scaling, improved performance as well as allowing for added functionalities. Unfortunately, commonly used high-k oxide deposition methods are not directly compatible with 2D materials. Here...