Publications by Dmitry Ovchinnikov

Non equilibrium anisotropic excitons in atomically thin ReS2

Andras Kis, Alessandro Surrente, Andrei Kucharavy, Dmitry Ovchinnikov

We present a systematic investigation of the electronic properties of bulk and few layer ReS2 van der Waals crystals using low temperature optical spectroscopy. Weak photoluminescence emission is observed from two non-degenerate band edge excitonic transit ...

IOP PUBLISHING LTD2019

Large-grain MBE-grown GaSe on GaAs with a Mexican hat-like valence band dispersion

Olivier Renault, Andras Kis, Ming-Wei Chen, Dmitry Ovchinnikov, Hokwon Kim

2018

Thickness-modulated metal-to-semiconductor transformation in a transition metal dichalcogenide

Andras Kis, Dmitry Ovchinnikov, Ahmet Avsar, Alberto Ciarrocchi

Nature Research2018

Field-induced charge separation dynamics in monolayer MoS2

Andras Kis, Dragan Mihailovic, Dmitry Ovchinnikov, Dumitru Dumcenco, Yen-Cheng Kung, Daniele Vella

The absorption spectra of 2D semiconductors are dominated by excitons with binding energy of several hundreds of meV. Nevertheless, even single layers show an appreciable photovoltaic effect and work as the active material in high sensitivity photodetector ...

Iop Publishing Ltd2017

2D transition metal dichalcogenides

Andras Kis, Oleg Yazyev, Diego José Pasquier, Sajedeh Manzeli, Dmitry Ovchinnikov

Graphene is very popular because of its many fascinating properties, but its lack of an electronic bandgap has stimulated the search for 2D materials with semiconducting character. Transition metal dichalcogenides (TMDCs), which are semiconductors of the t ...

Nature Publishing Group2017

Influence of structural and electrostatic disorder on transport properties of monolayers of two-dimensional semiconductors

Dmitry Ovchinnikov

Two-dimensional (2D) materials are under intensive investigation recently due to variety of electronic properties, ranging from insulators (h-BN) to semi-metals (graphene), semiconductors (MoS2, WSe2) with wide variability of band-gap and correlated phases ...

EPFL2017

Highly Oriented Atomically Thin Ambipolar MoSe2

Andras Kis, Oleg Yazyev, Alessandro Surrente, Philippe Gillet, Oriol López Sánchez, Ming-Wei Chen, Dmitry Ovchinnikov, Michele Pizzochero

Transition metal dichalcogenides (TMDCs), together with other two-dimensional (2D) materials, have attracted great interest due to the unique optical and electrical properties of atomically thin layers. In order to fulfill their potential, developing large ...

American Chemical Society2017

Suppressing Nucleation in Metal–Organic Chemical Vapor Deposition of MoS2

Andras Kis, Davide Deiana, Dmitry Ovchinnikov, Dmitrii Unuchek, Hokwon Kim

Toward the large-area deposition of MoS2 layers, we employ metal–organic precursors of Mo and S for a facile and reproducible van der Waals epitaxy on c-plane sapphire. Exposing c-sapphire substrates to alkali metal halide salts such as KI or NaCl together ...

American Chemical Society (ACS)2017

Valley polarization by spin injection in a light-emitting van der Waals heterojunction

Andras Kis, Oriol López Sánchez, Dmitry Ovchinnikov, Adrien Victor Allain, Shikhar Misra

The band structure of transition metal dichalcogenides (TMDCs) with valence band edges at different locations in the momentum space could be harnessed to build devices that operate relying on the valley degree of freedom. To realize such valleytronic devic ...

American Chemical Society (ACS)2016

Disorder engineering and conductivity dome in ReS2 with electrolyte gating

Andras Kis, Oleg Yazyev, Diego José Pasquier, Fernando Gargiulo, Dmitry Ovchinnikov, Adrien Victor Allain, Dumitru Dumcenco

Atomically thin rhenium disulphide (ReS2) is a member of the transition metal dichalcogenide family of materials. This two-dimensional semiconductor is characterized by weak interlayer coupling and a distorted 1T structure, which leads to anisotropy in ele ...

Nature Publishing Group2016

Single-layer MoS2 nanopores as nanopower generators

Andras Kis, Aleksandra Radenovic, Michael Graf, Dmitry Ovchinnikov, Jiandong Feng, Ke Liu, Dumitru Dumcenco

Making use of the osmotic pressure difference between fresh water and seawater is an attractive, renewable and clean way to generate power and is known as 'blue energy'(1-3). Another electrokinetic phenomenon, called the streaming potential, occurs when an ...

Nature Publishing Group2016

High-quality Synthetic 2D Transition Metal Dichalcogenide Semiconductors

Andras Kis, Dmitry Ovchinnikov, Dumitru Dumcenco, Kolyo Marinov

We give here an overview on our results on the large-area growth of 2D transition metal dichalcogenide semiconductors MoS2, MoSe2, WSe2 using chemical vapor deposition. The growth of MoS2 on sapphire occurs epitaxially with the crystalline orientation of t ...

Ieee2016

Large-Area Epitaxial Monolayer MoS2

Andras Kis, Aleksandra Radenovic, Anna Fontcuberta i Morral, Philippe Gillet, Nicola Marzari, Simone Bertolazzi, Oriol López Sánchez, Daria Krasnozhon, Ming-Wei Chen, Dmitry Ovchinnikov, Marco Gibertini, Dumitru Dumcenco, Yen-Cheng Kung, Kolyo Marinov

Two-dimensional semiconductors such as MoS2 are an emerging material family with wide-ranging potential applications in electronics, optoelectronics, and energy harvesting. Large-area growth methods are needed to open the way to applications. Control over ...

Amer Chemical Soc2015

Large-area MoS2 grown using H2S as the sulphur source

Andras Kis, Aleksandra Radenovic, Duncan Thomas Lindsay Alexander, Philippe Gillet, Oriol López Sánchez, Dmitry Ovchinnikov, Dumitru Dumcenco

We report on the growth of molybdenum disulphide (MoS2) using H2S as a gas-phase sulfur precursor that allows controlling the domain growth direction of domains in both vertical (perpendicular to the substrate plane) and horizontal (within the substrate pl ...

2015

Electrical Transport Properties of Single-Layer WS2

Andras Kis, Dmitry Ovchinnikov, Adrien Victor Allain, Dumitru Dumcenco

We report on the fabrication of field-effect transistors based on single layers and bilayers of the semiconductor WS2 and the investigation of their electronic transport properties. We find that the doping level strongly depends on the device environment a ...

Amer Chemical Soc2014