R. Gillen

activity

20092025

most citedPhotoluminescence of freestanding single- and few-layer MoS2

291 citations · 1.8k across the 32 of their papers we have counts for

collaborators

32 papers

cond-mat.mtrl-sci2025★ 2 cited

Unravelling the oxygen influence in cubic bixbyite In $_{2}$ O $_{3}$ on Raman active phonon modes by isotope studies

Johannes Feldl, Roland Gillen, Janina Maultzsch +5

In this study, we performed comprehensive investigations on the Raman active phonon modes in cubic bixbyite In $_{2}$ O $_{3}$ , an important oxide based, wide-bandgap semiconductor. Funda…

cond-mat.mes-hall2025

Semimetallic two-dimensional defective graphene networks with periodic 4-8 defect lines

Roland Gillen, Janina Maultzsch

We present theoretical simulations of the electronic properties of graphene-like two-dimensional (2D) carbon networks with a periodic arrangement of defect lines formed by alternat…

cond-mat.mtrl-sci2025★ 32 cited

Cove-edged Chiral Graphene Nanoribbons with Chirality-Dependent Bandgap and Carrier Mobility

K. Liu, W. Zheng, S. Osella +13

Graphene nanoribbons (GNRs) have garnered significant interest due to their highly customizable physicochemical properties and potential utility in nanoelectronics. Besides control…

cond-mat.str-el2024

Engineering correlated Dirac fermions and flat bands on SiC with transition-metal adatom lattices

Henri Menke, Niklas Enderlein, Roland Gillen +5

We propose three transition-metal adatom systems on SiC surfaces as a versatile platform to realize massless Dirac fermions and flat bands with strong electronic correlations. Usin…

cond-mat.mtrl-sci2024

Moiré lattice of twisted bilayer graphene as template for non-covalent functionalization

Tobias Dierke, Stefan Wolff, Roland Gillen +7

We present a novel approach to achieve spatial variations in the degree of non-covalent functionalization of twisted bilayer graphene (tBLG). The tBLG with twist angles varying bet…

cond-mat.mes-hall2024★ 9 cited

Hybrid moiré excitons and trions in twisted MoTe $_{2}$ -MoSe $_{2}$ heterobilayers

Shen Zhao, Xin Huang, Roland Gillen +8

We report experimental and theoretical studies of MoTe $_{2}$ -MoSe $_{2}$ heterobilayers with rigid moiré superlattices controlled by the twist angle. Using an effective continuum model…

cond-mat.mtrl-sci2023

Family behavior and Dirac bands in armchair nanoribbons with 4-8 defect lines

Roland Gillen, Janina Maultzsch

Bottom-up synthesis from molecular precursors is a powerful route for the creation of novel synthetic carbon-based low-dimensional materials, such as planar carbon lattices. The we…

cond-mat.mtrl-sci2023

Electronic Properties and Interlayer Interactions in Antimony Oxide Homo- and Heterobilayers

Stefan Wolff, Roland Gillen, Janina Maultzsch

Antimony shows promise as a two-dimensional (2D) mono-elemental crystal, referred to as antimonene. When exposed to ambient conditions, antimonene layers react with oxygen, forming…

cond-mat.mes-hall2023★ 3 cited

Robustness of momentum-indirect interlayer excitons in MoS2/WSe2 heterostructure against charge carrier doping

Ekaterina Khestanova, Tatyana Ivanova, Roland Gillen +13

Monolayer transition-metal dichalcogenide (TMD) semiconductors exhibit strong excitonic effects and hold promise for optical and optoelectronic applications. Yet, electron doping o…

cond-mat.mtrl-sci2022

First and Second Order Raman Spectroscopy of Monoclinic $β - Ga_{2} O_{3}$

Benjamin M. Janzen, Roland Gillen, Zbigniew Galazka +2

We employ a combined experimental-theoretical study of the first- and second-order Raman modes of monoclinic $β$ -Ga $_{2}$ O $_{3}$ . The investigated materials is of particular intere…

cond-mat.mes-hall2021★ 37 cited

Dark exciton-exciton annihilation in monolayer WSe $_{2}$

Daniel Erkensten, Samuel Brem, Koloman Wagner +8

The exceptionally strong Coulomb interaction in semiconducting transition-metal dichalcogenides (TMDs) gives rise to a rich exciton landscape consisting of bright and dark exciton…

cond-mat.mes-hall2021★ 12 cited

Interlayer excitonic spectra of vertically stacked MoSe $_{2}$ /WSe $_{2}$ heterobilayers

Roland Gillen

The optical spectra of vertically stacked MoSe $_{2}$ /WSe $_{2}$ heterostructures contain additional 'interlayer' excitonic peaks that are absent in the individual monolayer materials an…

cond-mat.mtrl-sci2020★ 45 cited

Isotopic study of Raman active phonon modes in $β$ -Ga $_{2}$ O $_{3}$

Benjamin M. Janzen, Piero Mazzolini, Roland Gillen +5

Holding promising applications in power electronics, the wide band gap material gallium oxide has emerged as a vital alternative to materials like GaN and SiC. The detailed study o…

cond-mat.mes-hall2020★ 84 cited

Hybridized intervalley moiré excitons and flat bands in twisted WSe $_{2}$ bilayers

Samuel Brem, Kai-Qiang Lin, Roland Gillen +4

The large surface-to-volume ratio in atomically thin 2D materials allows to efficiently tune their properties through modifications of their environment. Artificial stacking of two…

cond-mat.mtrl-sci2019★ 37 cited

Two-Dimensional Antimony Oxide

Stefan Wolff, Roland Gillen, Mhamed Assebban +2

Two-dimensional (2D) antimony, so-called antimonene, can form antimonene oxide when exposed to air. We present different types of single- and few-layer antimony oxide structures, b…

cond-mat.mtrl-sci2019

Vibrational signatures of diamondoid dimers with large intramolecular London dispersion interactions

Christoph Tyborski, Tobias Hueckstaedt, Roland Gillen +5

We analyze the vibrational properties of diamondoid compounds via Raman spectroscopy. The compounds are interconnected with carbon-carbon single bonds that exhibit exceptionally la…

cond-mat.mtrl-sci2018★ 79 cited

Phonon dispersion of MoS $_{2}$

Hans Tornatzky, Roland Gillen, Hiroshi Uchiyama +1

Transition metal dichalcogenides like MoS $_{2}$ , MoSe $_{2}$ , WS $_{2}$ , and WSe $_{2}$ have attracted enormous interest during recent years. They are van-der-Waals crystals with highly aniso…

cond-mat.mes-hall2018★ 113 cited

Interlayer excitons in MoSe $_{2}$ /WSe $_{2}$ heterostructures from first-principles

Roland Gillen, Janina Maultzsch

Based on \emph{ab initio} theoretical calculations of the optical spectra of vertical heterostructures of MoSe $_{2}$ (or MoS $_{2}$ ) and WSe $_{2}$ sheets, we reveal two spin-orbit-split R…

cond-mat.mtrl-sci2017★ 45 cited

Native point defects of semiconducting layered Bi2O2Se

Huanglong Li, Xintong Xu, Yi Zhang +3

Bi2O2Se is an emerging semiconducting, air-stable layered material (Nat. Nanotechnol. 2017, 12, 530; Nano Lett. 2017, 17, 3021), potentially exceeding MoS2 and phosphorene in elect…

cond-mat.mtrl-sci2016★ 65 cited

Light-Matter Interactions in Two-Dimensional Transition Metal Dichalcogenides: Dominant Excitonic Transitions in mono- and few-layer MoX $_{2}$ and Band Nesting

Roland Gillen, Janina Maultzsch

We report ab initio calculations of the dielectric function of six mono- and bilayer molybdenum dichalcogenides based in a Bethe Salpether equation+G $_{0}$ W $_{0}$ ansatz, focussing on…

cond-mat.mes-hall2015★ 91 cited

Splitting of the monolayer out-of-plane A'1 Raman mode in few-layer WS2

Matthias Staiger, Roland Gillen, Nils Scheuschner +5

We present Raman measurements of mono- and few-layer WS2. We study the monolayer A'1 mode around 420 cm(-1) and its evolution with the number of layers. We show that with increasin…

cond-mat.mtrl-sci2015★ 104 cited

Newly observed first-order resonant Raman modes in few-layer MoS $_{2}$

Nils Scheuschner, Roland Gillen, Matthias Staiger +1

We report two new first-order Raman modes in the spectra of few-layer MoS $_{2}$ at 286~cm $^{- 1}$ and 471~cm $^{- 1}$ for excitation energies above 2.4~eV. These modes appear only in fe…

cond-mat.mtrl-sci2015★ 25 cited

Beyond double-resonant Raman scattering: UV Raman spectroscopy on graphene, graphite and carbon nanotubes

Christoph Tyborski, Felix Herziger, Roland Gillen +1

We present an analysis of deep-UV Raman measurements of graphite, graphene and carbon nanotubes. For excitation energies above the strong optical absorption peak at the $M$ point i…

cond-mat.mes-hall2014★ 43 cited

Indirect doping effects from impurities in MoS $_{2}$ /BN heterostructures

Roland Gillen, John Robertson, Janina Maultzsch

We performed density functional theory calculations on heterostructures of single layers of hexagonal BN and MoS $_{2}$ to assess the effect of doping in the BN sheet and of interstit…

Unravelling the oxygen influence in cubic bixbyite In2​O3​ on Raman active phonon modes by isotope studies

Semimetallic two-dimensional defective graphene networks with periodic 4-8 defect lines

Cove-edged Chiral Graphene Nanoribbons with Chirality-Dependent Bandgap and Carrier Mobility

Engineering correlated Dirac fermions and flat bands on SiC with transition-metal adatom lattices

Moiré lattice of twisted bilayer graphene as template for non-covalent functionalization

Hybrid moiré excitons and trions in twisted MoTe2​-MoSe2​ heterobilayers

Family behavior and Dirac bands in armchair nanoribbons with 4-8 defect lines

Electronic Properties and Interlayer Interactions in Antimony Oxide Homo- and Heterobilayers

Robustness of momentum-indirect interlayer excitons in MoS2/WSe2 heterostructure against charge carrier doping

First and Second Order Raman Spectroscopy of Monoclinic β−Ga2​O3​

Dark exciton-exciton annihilation in monolayer WSe2​

Interlayer excitonic spectra of vertically stacked MoSe2​/WSe2​ heterobilayers

Isotopic study of Raman active phonon modes in β-Ga2​O3​

Hybridized intervalley moiré excitons and flat bands in twisted WSe2​ bilayers

Two-Dimensional Antimony Oxide

Vibrational signatures of diamondoid dimers with large intramolecular London dispersion interactions

Phonon dispersion of MoS2​

Interlayer excitons in MoSe2​/WSe2​ heterostructures from first-principles

Native point defects of semiconducting layered Bi2O2Se

Light-Matter Interactions in Two-Dimensional Transition Metal Dichalcogenides: Dominant Excitonic Transitions in mono- and few-layer MoX2​ and Band Nesting

Splitting of the monolayer out-of-plane A'1 Raman mode in few-layer WS2

Newly observed first-order resonant Raman modes in few-layer MoS2​

Beyond double-resonant Raman scattering: UV Raman spectroscopy on graphene, graphite and carbon nanotubes

Indirect doping effects from impurities in MoS2​/BN heterostructures

Unravelling the oxygen influence in cubic bixbyite In $_{2}$ O $_{3}$ on Raman active phonon modes by isotope studies

Hybrid moiré excitons and trions in twisted MoTe $_{2}$ -MoSe $_{2}$ heterobilayers

First and Second Order Raman Spectroscopy of Monoclinic $β - Ga_{2} O_{3}$

Dark exciton-exciton annihilation in monolayer WSe $_{2}$

Interlayer excitonic spectra of vertically stacked MoSe $_{2}$ /WSe $_{2}$ heterobilayers

Isotopic study of Raman active phonon modes in $β$ -Ga $_{2}$ O $_{3}$

Hybridized intervalley moiré excitons and flat bands in twisted WSe $_{2}$ bilayers

Phonon dispersion of MoS $_{2}$

Interlayer excitons in MoSe $_{2}$ /WSe $_{2}$ heterostructures from first-principles

Light-Matter Interactions in Two-Dimensional Transition Metal Dichalcogenides: Dominant Excitonic Transitions in mono- and few-layer MoX $_{2}$ and Band Nesting

Newly observed first-order resonant Raman modes in few-layer MoS $_{2}$

Indirect doping effects from impurities in MoS $_{2}$ /BN heterostructures