All Outputs (51)

Thermally stable quantum Hall effect in a gated ferroelectric-graphene heterostructure (2023)
Journal Article

The quantum Hall effect is widely used for the investigation of fundamental phenomena, ranging from topological phases to composite fermions. In particular, the discovery of a room temperature resistance quantum in graphene is significant for compact... Read More about Thermally stable quantum Hall effect in a gated ferroelectric-graphene heterostructure.

A magnetically-induced Coulomb gap in graphene due to electron-electron interactions (2023)
Journal Article

Insights into the fundamental properties of graphene’s Dirac-Weyl fermions have emerged from studies of electron tunnelling transistors in which an atomically thin layer of hexagonal boron nitride (hBN) is sandwiched between two layers of high purity... Read More about A magnetically-induced Coulomb gap in graphene due to electron-electron interactions.

Graphene FETs with high and low mobilities have universal temperature-dependent properties (2023)
Journal Article

We use phenomenological modelling and detailed experimental studies of charge carrier transport to investigate the dependence of the electrical resistivity,ρ, on gate voltage,Vg, for a series of monolayer graphene field effect transistors with mobili... Read More about Graphene FETs with high and low mobilities have universal temperature-dependent properties.

Exciton and Phonon Radiative Linewidths in Monolayer Boron Nitride (2022)
Journal Article

The light-matter interaction in bulk semiconductors is in the strong coupling regime with hybrid eigenstates, the so-called exciton-polaritons and phonon-polaritons. In two-dimensional (2D) systems, the translational invariance is broken in the direc... Read More about Exciton and Phonon Radiative Linewidths in Monolayer Boron Nitride.

Exciton and Phonon Radiative Linewidths in Monolayer Boron Nitride (2022)
Journal Article

The light-matter interaction in bulk semiconductors is in the strong-coupling regime with hybrid eigenstates, the so-called exciton polaritons and phonon polaritons. In two-dimensional (2D) systems, the translational invariance is broken in the direc... Read More about Exciton and Phonon Radiative Linewidths in Monolayer Boron Nitride.

Graphene’s non-equilibrium fermions reveal Doppler-shifted magnetophonon resonances accompanied by Mach supersonic and Landau velocity effects (2021)
Journal Article

Oscillatory magnetoresistance measurements on graphene have revealed a wealth of novel physics. These phenomena are typically studied at low currents. At high currents, electrons are driven far from equilibrium with the atomic lattice vibrations so t... Read More about Graphene’s non-equilibrium fermions reveal Doppler-shifted magnetophonon resonances accompanied by Mach supersonic and Landau velocity effects.

Heavy carrier effective masses in van der Waals semiconductor Sn(SeS) revealed by high magnetic fields up to 150 T (2021)
Journal Article

The SnSe2(1-x)S2x alloy is a van der Waals semiconductor with versatile, tunable electronic properties and prospects for future applications ranging from electronics to thermoelectrics and superconductivity. Its band structure and carrier effective m... Read More about Heavy carrier effective masses in van der Waals semiconductor Sn(SeS) revealed by high magnetic fields up to 150 T.

Epitaxy of boron nitride monolayers for graphene-based lateral heterostructures (2021)
Journal Article

Monolayers of hexagonal boron nitride (hBN) are grown on graphite substrates using high-temperature molecular beam epitaxy (HT-MBE). The hBN monolayers are observed to grow predominantly from step edges on the graphite surface and exhibit a strong de... Read More about Epitaxy of boron nitride monolayers for graphene-based lateral heterostructures.

Step-Flow Growth of Graphene-Boron Nitride Lateral Heterostructures by Molecular Beam Epitaxy (2020)
Journal Article

Integration of graphene and hexagonal boron nitride (hBN) into lateral heterostructures has drawn focus due to the ability to broadly engineer the material properties. Hybrid monolayers with tuneable bandgaps have been reported, while the interface i... Read More about Step-Flow Growth of Graphene-Boron Nitride Lateral Heterostructures by Molecular Beam Epitaxy.

Resonant tunnelling into the two-dimensional subbands of InSe layers (2020)
Journal Article

Two-dimensional (2D) van der Waals (vdW) crystals have attracted considerable interest for digital electronics beyond Si-based complementary metal oxide semiconductor technologies. Despite the transformative success of Si-based devices, there are lim... Read More about Resonant tunnelling into the two-dimensional subbands of InSe layers.

Van der Waals SnSe2(1-x)S2x alloys: composition-dependent bowing coefficient and electron-phonon interaction (2020)
Journal Article

The design of advanced functional materials with customized properties often requires the use of an alloy. This approach has been used for decades, but only recently to create van der Waals (vdW) alloys for applications in electronics, optoelectronic... Read More about Van der Waals SnSe2(1-x)S2x alloys: composition-dependent bowing coefficient and electron-phonon interaction.

Defect-assisted high photoconductive UV-VIS gain in perovskite-decorated graphene transistors (2019)
Journal Article

Recent progress in the synthesis of high stability inorganic perovskite nanocrystals (NCs) has led to their increasing use in broadband photodetectors. These NCs are of particular interest for the UV range as they have the potential to extend the wav... Read More about Defect-assisted high photoconductive UV-VIS gain in perovskite-decorated graphene transistors.

Magnetophonon spectroscopy of Dirac fermion scattering by transverse and longitudinal acoustic phonons in graphene (2019)
Journal Article

Recently observed magnetophonon resonances in the magnetoresistance of graphene are investigated using the Kubo formalism. This analysis provides a quantitative fit to the magnetophonon resonances over a wide range of carrier densities. It demonstrat... Read More about Magnetophonon spectroscopy of Dirac fermion scattering by transverse and longitudinal acoustic phonons in graphene.

Two-Dimensional Covalent Crystals by Chemical Conversion of Thin van der Waals Materials (2019)
Journal Article

Most of the studied two-dimensional (2D) materials have been obtained by exfoliation of van der Waals crystals. Recently, there has been growing interest in fabricating synthetic 2D crystals which have no layered bulk analogues. These efforts have be... Read More about Two-Dimensional Covalent Crystals by Chemical Conversion of Thin van der Waals Materials.

Strong magnetophonon oscillations in extra-large graphene (2019)
Journal Article

Van der Waals materials and their heterostructures offer a versatile platform for studying a variety of quantum transport phenomena due to their unique crystalline properties and the exceptional ability in tuning their electronic spectrum. However, m... Read More about Strong magnetophonon oscillations in extra-large graphene.

Direct band-gap crossover in epitaxial monolayer boron nitride (2019)
Journal Article

Hexagonal boron nitride is a large band-gap insulating material which complements the electronic and optical properties of graphene and the transition metal dichalcogenides. However, the intrinsic optical properties of monolayer boron nitride remain... Read More about Direct band-gap crossover in epitaxial monolayer boron nitride.

Tunnel spectroscopy of localised electronic states in hexagonal boron nitride (2018)
Journal Article

Hexagonal boron nitride is a large band gap layered crystal, frequently incorporated in van der Waals heterostructures as an insulating or tunnel barrier. Localised states with energies within its band gap can emit visible light, relevant to applicat... Read More about Tunnel spectroscopy of localised electronic states in hexagonal boron nitride.

Photo-quantum Hall effect and light-induced charge transfer at the interface of graphene/InSe heterostructures (2018)
Journal Article

The transfer of electronic charge across the interface of two van der Waals crystals can underpin the operation of a new class of functional devices. Amongst van der Waals semiconductors, an exciting and rapidly growing development involves the “post... Read More about Photo-quantum Hall effect and light-induced charge transfer at the interface of graphene/InSe heterostructures.

High-temperature molecular beam epitaxy of hexagonal boron nitride with high active nitrogen fluxes (2018)
Journal Article

Hexagonal boron nitride (hBN) has attracted much attention as a key component in van der Waals heterostructures and as a wide band gap material for deep-ultraviolet devices. We have recently demonstrated plasma-assisted molecular beam epitaxy (PA-MBE... Read More about High-temperature molecular beam epitaxy of hexagonal boron nitride with high active nitrogen fluxes.

Moiré-modulated conductance of hexagonal boron nitride tunnel barriers (2018)
Journal Article

Monolayer hexagonal boron nitride (hBN) tunnel barriers investigated using conductive atomic force microscopy reveal moiré patterns in the spatial maps of their tunnel conductance consistent with the formation of a moiré superlattice between the hB... Read More about Moiré-modulated conductance of hexagonal boron nitride tunnel barriers.