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@article{WOS:001701838600001,
title = {Surface defects in carbon-doped hexagonal boron nitride for
negative-contrast direct laser writing},
author = {Dmitrii Litvinov and Virgil Gavriliuc and Magdalena Grzeszczyk and Kristina Vaklinova and Kenji Watanabe and Takashi Taniguchi and Kostya S Novoselov and Maciej Koperski},
doi = {10.1088/2053-1583/ae463c},
times_cited = {0},
issn = {2053-1583},
year = {2026},
date = {2026-06-01},
journal = {2D MATERIALS},
volume = {13},
number = {2},
publisher = {IOP Publishing Ltd},
address = {No.2 The Distillery, Glassfields, Avon Street, Bristol, ENGLAND},
abstract = {Radiative defects in hexagonal boron nitride (hBN) are active in a broad
spectral range from deep ultraviolet to near-infrared wavelengths.
Representatives of these defects act as bright single photon sources,
spin-1 systems, and multiproperty atomic-scale sensors. They are
predominantly investigated in bulk hBN films, where defects are
decoupled from surface and interfacial effects. Here, we demonstrate a
novel class of surface defects optically active in the green/yellow
visible spectral range, which exhibit photophysical properties distinct
from their bulk counterparts. High-power resonant laser illumination
quenched the emission from the ensemble of such defects, which was
attributed to a light-driven structural reconfiguration. The quenched
defects were found to recover their emissive capabilities via a thermal
cycling process, revealing an activation energy of 24.5 meV for the
structural transition. Alternatively, permanent quenching of the defects
was triggered by surface chemistry, involving lithiation-enabled
attachment of functional groups. These mechanisms were utilized to
realize negative-contrast direct laser writing, designing arbitrary
geometric emissive patterns on demand in a microscopic configuration.
The surface-active radiative centers in hBN appear particularly
attractive for exploring environmental sensitivity, surface science, and
coupling to photonic structures or electronic devices by taking unique
advantage of the two-dimensional characteristics of the host lattice.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

@article{WOS:001680918000001,
title = {Breaking the 2-nm Barrier in Hard Disk Drives Using Monolayer Amorphous
Carbon Overcoats},
author = {Hongji Zhang and Artem K Grebenko and Dmitrii Litvinov and Wenwen Zheng and Konstantin V Iakoubovskii and Sergey Y Grebenchuk and Anna Makarova and Alexander Fedorov and Andrei Starkov and Carlo M Orofeo and Denis V Vyalikh and Mario Lanza and Maciej Koperski and Kostya S Novoselov and Chee-tat Toh and Barbaros Ozyilmaz},
doi = {10.1002/adma.202519149},
times_cited = {0},
issn = {0935-9648},
year = {2026},
date = {2026-03-01},
journal = {ADVANCED MATERIALS},
volume = {38},
number = {15},
publisher = {WILEY-V C H VERLAG GMBH},
address = {POSTFACH 101161, 69451 WEINHEIM, GERMANY},
abstract = {The rapid growth of artificial intelligence (AI) has increased the
demand for large-scale data storage, making hard disk drives (HDDs)
indispensable in data centers due to their cost-effectiveness and
stability. To support AI-driven data requirements, increasing the areal
storage density is critical. However, this metric is increasingly
constrained by the carbon overcoat (COC), the essential protective layer
for magnetic media. Traditional diamond-like carbon (DLC) can no longer
fulfill the stringent demands for ultrathin coatings and high thermal
stability required by next-generation technologies like Heat-Assisted
Magnetic Recording (HAMR) and bit-patterned media. Here, we introduce
monolayer amorphous carbon (MAC) as a superior alternative. MAC is
directly grown on the heterogeneous (Fe, Pt, SiO2) HDD surface at low
temperatures (similar to 300 degrees C), achieving an uniform 0.8 nm
thickness across 2.5-inch disks. Despite its atomic thickness, MAC
demonstrates high corrosion resistance and low roughness comparable to
commercial 2.5 nm COCs. Its fully amorphous, sp2-hybridized structure
ensures excellent thermal stability under HAMR-like conditions (similar
to 450 degrees C) and a low friction coefficient, enabling potential
lubricant-free operation. Replacing traditional COCs with MAC
facilitates the development of HDD media capable of achieving 10 Tb/in2,
addressing the urgent storage demands of the digital era.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

@article{WOS:001619984500001,
title = {Two-Dimensional Materials as a Multiproperty Sensing Platform},
author = {Dipankar Jana and Shubhrasish Mukherjee and Dmitrii Litvinov and Magdalena Grzeszczyk and Sergey Grebenchuk and Makars Siskins and Virgil Gavriliuc and Yihang Ouyang and Changyi Chen and Yuxuan Ye and Meng Yiming and Maciej Koperski},
doi = {10.1002/adfm.202516728},
times_cited = {3},
issn = {1616-301X},
year = {2026},
date = {2026-02-01},
journal = {ADVANCED FUNCTIONAL MATERIALS},
volume = {36},
number = {14},
publisher = {WILEY-V C H VERLAG GMBH},
address = {POSTFACH 101161, 69451 WEINHEIM, GERMANY},
abstract = {Two-dimensional (2D) materials have disrupted materials science due to
the development of van der Waals technology. It enables the stacking of
ultrathin layers of materials characterized by vastly different
electronic structures to create man-made heterostructures and devices
with rationally tailored properties, circumventing limitations of
matching crystal structures, lattice constants, and geometry of
constituent materials and supporting substrates. 2D materials exhibit
extraordinary mechanical flexibility, strong light-matter interactions
driven by their excitonic response, single photon emission from atomic
centers, stable ferromagnetism in sub-nm thin films, fractional quantum
Hall effect in high-quality devices, and chemoselectivity at ultrahigh
surface-to-volume ratio. Consequently, van der Waals heterostructures
with atomically flat interfaces demonstrate an unprecedented degree of
intertwined mechanical, chemical, optoelectronic, and magnetic
properties. This constitutes a foundation for multiproperty sensing,
based on complex intra- and intermaterial interactions, and a robust
response to external stimuli originating from the environment. Here,
recent progress are reviewed in the development of sensing applications
with 2D materials, highlighting the areas where van der Waals
heterostructures offer the highest sensitivity, simultaneous responses
to multiple distinct externalities due to their atomic thickness in
conjunction with unique material combinations, and conceptually new
sensing methodology.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

@article{WOS:001575556400001,
title = {Roadmap for Photonics with 2D Materials},
author = {Javier F Garcia de Abajo and D N Basov and Frank H L Koppens and Lorenzo Orsini and Matteo Ceccanti and Sebastian Castilla and Lorenzo Cavicchi and Marco Polini and P A D Goncalves and A T Costa and N M R Peres and Asger N Mortensen and Sathwik Bharadwaj and Zubin Jacob and P J Schuck and A N Pasupathy and Milan Delor and M K Liu and Aitor Mugarza and Pablo Merino and Marc G Cuxart and Emigdio Chavez-Angel and Martin Svec and Luiz H G Tizei and Florian Dirnberger and Hui Deng and Christian Schneider and Vinod Menon and Thorsten Deilmann and Alexey Chernikov and Kristian S Thygesen and Yohannes Abate and Mauricio Terrones and Vinod K Sangwan and Mark C Hersam and Leo Yu and Xueqi Chen and Tony F Heinz and Puneet Murthy and Martin Kroner and Tomasz Smolenski and Deepankur Thureja and Thibault Chervy and Armando Genco and Chiara Trovatello and Giulio Cerullo and Stefano Dal Conte and Daniel Timmer and Antonietta De Sio and Christoph Lienau and Nianze Shang and Hao Hong and Kaihui Liu and Zhipei Sun and Lee A Rozema and Philip Walther and Andrea Alu and Andrea Marini and Michele Cotrufo and Raquel Queiroz and X -Y Zhu and Joel D Cox and Eduardo J C Dias and Alvaro Rodriguez Echarri and Fadil Iyikanat and Paul Herrmann and Nele Tornow and Sebastian Klimmer and Jan Wilhelm and Giancarlo Soavi and Zeyuan Sun and Shiwei Wu and Ying Xiong and Oles Matsyshyn and Roshan Krishna Kumar and Justin C W Song and Tomer Bucher and Alexey Gorlach and Shai Tsesses and Ido Kaminer and Julian Schwab and Florian Mangold and Harald Giessen and M Sanchez Sanchez and D K Efetov and T Low and G Gomez-Santos and T Stauber and Gonzalo Alvarez-Perez and Jiahua Duan and Luis Martin-Moreno and Alexander Paarmann and Joshua D Caldwell and Alexey Y Nikitin and Pablo Alonso-Gonzalez and Niclas S Mueller and Valentyn Volkov and Deep Jariwala and Timur Shegai and Jorik van de Groep and Alexandra Boltasseva and Igor V Bondarev and Vladimir M Shalaev and Jeffrey Simon and Colton Fruhling and Guangzhen Shen and Dino Novko and Shijing Tan and Bing Wang and Hrvoje Petek and Vahagn Mkhitaryan and Renwen Yu and Alejandro Manjavacas and Enrique J Ortega and Xu Cheng and Ruijuan Tian and Dong Mao and Dries Van Thourhout and Xuetao Gan and Qing Dai and Aaron Sternbach and You Zhou and Mohammad Hafezi and Dmitrii Litvinov and Magdalena Grzeszczyk and Kostya S Novoselov and Maciej Koperski and Sotirios Papadopoulos and Lukas Novotny and Leonardo Viti and Miriam Serena Vitiello and Nathan D Cottam and Benjamin T Dewes and Oleg Makarovsky and Amalia Patane and Yihao Song and Mingyang Cai and Jiazhen Chen and Doron Naveh and Houk Jang and Suji Park and Fengnian Xia and Philipp K Jenke and Josip Bajo and Benjamin Braun and Kenneth S Burch and Liuyan Zhao and Xiaodong Xu},
doi = {10.1021/acsphotonics.5c00353},
times_cited = {39},
issn = {2330-4022},
year = {2025},
date = {2025-08-01},
journal = {ACS PHOTONICS},
volume = {12},
number = {8},
pages = {3961-4095},
publisher = {AMER CHEMICAL SOC},
address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA},
abstract = {Triggered by advances in atomic-layer exfoliation and growth techniques,
along with the identification of a wide range of extraordinary physical
properties in self-standing films consisting of one or a few atomic
layers, two-dimensional (2D) materials such as graphene, transition
metal dichalcogenides (TMDs), and other van der Waals (vdW) crystals now
constitute a broad research field expanding in multiple directions
through the combination of layer stacking and twisting, nanofabrication,
surface-science methods, and integration into nanostructured
environments. Photonics encompasses a multidisciplinary subset of those
directions, where 2D materials contribute remarkable nonlinearities,
long-lived and ultraconfined polaritons, strong excitons, topological
and chiral effects, susceptibility to external stimuli, accessibility,
robustness, and a completely new range of photonic materials based on
layer stacking, gating, and the formation of moire patterns. These
properties are being leveraged to develop applications in
electro-optical modulation, light emission and detection, imaging and
metasurfaces, integrated optics, sensing, and quantum physics across a
broad spectral range extending from the far-infrared to the ultraviolet,
as well as enabling hybridization with spin and momentum textures of
electronic band structures and magnetic degrees of freedom. The rapid
expansion of photonics with 2D materials as a dynamic research arena is
yielding breakthroughs, which this Roadmap summarizes while identifying
challenges and opportunities for future goals and how to meet them
through a wide collection of topical sections prepared by leading
practitioners.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

@article{WOS:001465855100001,
title = {Site-Selective Creation of Blue Emitters in Hexagonal Boron Nitride},
author = {Haidong Liang and Yuan Chen and Leyi Loh and Nicholas Lin Quan Cheng and Dmitrii Litvinov and Chengyuan Yang and Yifeng Chen and Zhepeng Zhang and Kenji Watanabe and Takashi Taniguchi and Maciej Koperski and Su Ying Quek and Michel Bosman and Goki Eda and Andrew Anthony Bettiol},
doi = {10.1021/acsnano.5c03423},
times_cited = {8},
issn = {1936-0851},
year = {2025},
date = {2025-04-01},
journal = {ACS NANO},
volume = {19},
number = {15},
pages = {15130-15138},
publisher = {AMER CHEMICAL SOC},
address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA},
abstract = {Hexagonal boron nitride (hBN) has been of great interest due to its
ability to host several bright quantum emitters at room temperature.
However, the identification of the observed emitters remains challenging
due to spectral variability, as well as the lack of atomic defect
structure information. In this work, we demonstrate the site-selective
creation of blue emitters in exfoliated hBN flakes with high-energy ion
irradiation. With the correlation analysis of cryogenic and
temperature-dependent photoluminescence (PL) spectroscopy, we observe
two zero phonon lines (ZPLs) at similar to 432.8 and 454.3 nm.
Photoluminescence excitation (PLE) measurements further confirm the
emission origins of the two prominent lines. Scanning transmission
electron microscopy (STEM) reveals that the dominant defect structures
present in ion-irradiated samples are vacancy-type (V x ) and
adatom(intercalant)-type (A x ). Together with first-principles GW-BSE
(Bethe-Salpeter equation) calculations, we deduce that the observed blue
emissions are likely related to boron intercalants (Bint). Our results
not only discover a group of blue emissions in hBN but also provide
insights into the physical origin of the emissions with local atomic
structures in hBN.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}