2026
|
Zawadzka, Natalia; Litvinov, Dmitrii; Kwast, Stan; Baranov, Denis; Rosner, Malte; Molas, Maciej R; Koperski, Maciej; Grzeszczyk, Magdalena Defect-Induced Single-Photon Emission in ZnPS3 ACS NANO, 2026, DOI: 10.1021/acsnano.5c19936. Abstract | BibTeX | Endnote @article{WOS:001794805000001,
title = {Defect-Induced Single-Photon Emission in ZnPS3},
author = {Natalia Zawadzka and Dmitrii Litvinov and Stan Kwast and Denis Baranov and Malte Rosner and Maciej R Molas and Maciej Koperski and Magdalena Grzeszczyk},
doi = {10.1021/acsnano.5c19936},
times_cited = {0},
issn = {1936-0851},
year = {2026},
date = {2026-06-01},
journal = {ACS NANO},
publisher = {AMER CHEMICAL SOC},
address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA},
abstract = {Research on single photon sources in layered materials has been limited
so far to transition metal dichalcogenides (TMDs) and hexagonal boron
nitride (hBN) as hosting platforms. These quantum emitters exhibit
advantages due to the distinct semiconducting and insulating
characteristics of the two classes of materials, which enable their
integration with van der Waals heterostructures and devices. Here, we
report single photon emission in ZnPS3, which belongs to the MPX3 family
characterized by stronger electronic correlations than those observed
intrinsically in TMDs or hBN. We provide a comprehensive
characterization of the vibrational and optical properties of
nonmagnetic ZnPS3 crystals, focusing on unraveling the mechanisms
responsible for the single photon emission. Using polarization-resolved
Raman scattering spectroscopy, we identify key phonon modes and uncover
strong metal-ligand interactions that influence both phonon dynamics and
defect-bound excitonic states. Low-temperature photoluminescence
spectroscopy reveals stable and narrow optical transitions localized at
defect sites, while second-order correlation measurements confirm the
quantum nature of the emission. We complement our experimental analysis
with ab initio density functional and GW many-body perturbation theory
calculations to investigate the characteristics of the bulk and
defect-related electronic structure. Our theoretical analysis reveals
that phosphorus vacancies introduce midgap states, enabling optical
transitions occurring at the energy range consistent with the
experimentally observed emission lines. This joint approach identifies
P-vacancies as the likely origin of single photon emitters in ZnPS3.
Furthermore, we anticipate that similar behavior should be present in
other MPX3 compounds, offering a framework for exploring defect-based
quantum emitters with intrinsic magnetic tunability.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Research on single photon sources in layered materials has been limited
so far to transition metal dichalcogenides (TMDs) and hexagonal boron
nitride (hBN) as hosting platforms. These quantum emitters exhibit
advantages due to the distinct semiconducting and insulating
characteristics of the two classes of materials, which enable their
integration with van der Waals heterostructures and devices. Here, we
report single photon emission in ZnPS3, which belongs to the MPX3 family
characterized by stronger electronic correlations than those observed
intrinsically in TMDs or hBN. We provide a comprehensive
characterization of the vibrational and optical properties of
nonmagnetic ZnPS3 crystals, focusing on unraveling the mechanisms
responsible for the single photon emission. Using polarization-resolved
Raman scattering spectroscopy, we identify key phonon modes and uncover
strong metal-ligand interactions that influence both phonon dynamics and
defect-bound excitonic states. Low-temperature photoluminescence
spectroscopy reveals stable and narrow optical transitions localized at
defect sites, while second-order correlation measurements confirm the
quantum nature of the emission. We complement our experimental analysis
with ab initio density functional and GW many-body perturbation theory
calculations to investigate the characteristics of the bulk and
defect-related electronic structure. Our theoretical analysis reveals
that phosphorus vacancies introduce midgap states, enabling optical
transitions occurring at the energy range consistent with the
experimentally observed emission lines. This joint approach identifies
P-vacancies as the likely origin of single photon emitters in ZnPS3.
Furthermore, we anticipate that similar behavior should be present in
other MPX3 compounds, offering a framework for exploring defect-based
quantum emitters with intrinsic magnetic tunability. - FNClarivate Analytics Web of Science
- VR1.0
- PTJ
- AFNatalia Zawadzka
Dmitrii Litvinov
Stan Kwast
Denis Baranov
Malte Rosner
Maciej R Molas
Maciej Koperski
Magdalena Grzeszczyk
- TIDefect-Induced Single-Photon Emission in ZnPS3
- SOACS NANO
- DTArticle
- ABResearch on single photon sources in layered materials has been limited
so far to transition metal dichalcogenides (TMDs) and hexagonal boron
nitride (hBN) as hosting platforms. These quantum emitters exhibit
advantages due to the distinct semiconducting and insulating
characteristics of the two classes of materials, which enable their
integration with van der Waals heterostructures and devices. Here, we
report single photon emission in ZnPS3, which belongs to the MPX3 family
characterized by stronger electronic correlations than those observed
intrinsically in TMDs or hBN. We provide a comprehensive
characterization of the vibrational and optical properties of
nonmagnetic ZnPS3 crystals, focusing on unraveling the mechanisms
responsible for the single photon emission. Using polarization-resolved
Raman scattering spectroscopy, we identify key phonon modes and uncover
strong metal-ligand interactions that influence both phonon dynamics and
defect-bound excitonic states. Low-temperature photoluminescence
spectroscopy reveals stable and narrow optical transitions localized at
defect sites, while second-order correlation measurements confirm the
quantum nature of the emission. We complement our experimental analysis
with ab initio density functional and GW many-body perturbation theory
calculations to investigate the characteristics of the bulk and
defect-related electronic structure. Our theoretical analysis reveals
that phosphorus vacancies introduce midgap states, enabling optical
transitions occurring at the energy range consistent with the
experimentally observed emission lines. This joint approach identifies
P-vacancies as the likely origin of single photon emitters in ZnPS3.
Furthermore, we anticipate that similar behavior should be present in
other MPX3 compounds, offering a framework for exploring defect-based
quantum emitters with intrinsic magnetic tunability. - Z90
- PUAMER CHEMICAL SOC
- PA1155 16TH ST, NW, WASHINGTON, DC 20036 USA
- SN1936-0851
- DI10.1021/acsnano.5c19936
- UTWOS:001794805000001
- ER
- EF
|
Ramasubramanian, Brindha; Dutta, Rajdeep; Koperski, Maciej; Chellappan, Vijila; Senthilnath, J Multi-property optimization for designing carbon electrodes JOURNAL OF POWER SOURCES, 676 , 2026, DOI: 10.1016/j.jpowsour.2026.239872. Abstract | BibTeX | Endnote @article{WOS:001730079900001,
title = {Multi-property optimization for designing carbon electrodes},
author = {Brindha Ramasubramanian and Rajdeep Dutta and Maciej Koperski and Vijila Chellappan and J Senthilnath},
doi = {10.1016/j.jpowsour.2026.239872},
times_cited = {0},
issn = {0378-7753},
year = {2026},
date = {2026-06-01},
journal = {JOURNAL OF POWER SOURCES},
volume = {676},
publisher = {ELSEVIER},
address = {RADARWEG 29, 1043 NX AMSTERDAM, NETHERLANDS},
abstract = {In this paper, we propose a novel approach termed as Multi-Property
Optimization of Estimated Symbolic Expressions (MPOESE) to
systematically optimize carbon electrode properties using a dataset
comprising 300 data points compiled from the literature spanning from
2005 to 2025. The dataset captures key input parameters, including
precursor type, synthesis method, activation temperature, process time,
activation agents, and atmospheric conditions alongside output
parameters such as specific surface area, pore volume, and particle
size. The proposed approach, MPOESE, leverages the strengths of symbolic
regression (SR) to estimate mathematical expressions of multiple outputs
and Bayesian Optimization (BO) to determine their optimal values. Using
limited data available in the literature, MPOESE estimates nonlinear
relations and multivariate dependencies between the variable synthesis
conditions that are not readily discernible through traditional
trial-and-error experimentation or statistical regression. These
estimated functional mappings allow the adopted multi-objective BO
technique to explore the material search space and find the optimal set
of solutions. Among them, one specific solution using plastic as the
precursor material was selected for its ease of availability and was
experimentally validated. The results imply that under controlled
pyrolysis with KOH activation at 700 degrees C and moderate dwell time
(similar to 1 h), these feed stocks can yield carbons with exceptionally
high microporosity (>1.2 cm(3) g(-1)) and surface areas above 1150 m(2)
g(-1). This study underscores the role of symbolic approximation and
multi-objective optimization in navigating complex material design
space, enabling rapid evidence-based recommendations for sustainable
precursors, and accelerating the rational design of high-performance
carbon architectures for electrochemical energy storage systems.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In this paper, we propose a novel approach termed as Multi-Property
Optimization of Estimated Symbolic Expressions (MPOESE) to
systematically optimize carbon electrode properties using a dataset
comprising 300 data points compiled from the literature spanning from
2005 to 2025. The dataset captures key input parameters, including
precursor type, synthesis method, activation temperature, process time,
activation agents, and atmospheric conditions alongside output
parameters such as specific surface area, pore volume, and particle
size. The proposed approach, MPOESE, leverages the strengths of symbolic
regression (SR) to estimate mathematical expressions of multiple outputs
and Bayesian Optimization (BO) to determine their optimal values. Using
limited data available in the literature, MPOESE estimates nonlinear
relations and multivariate dependencies between the variable synthesis
conditions that are not readily discernible through traditional
trial-and-error experimentation or statistical regression. These
estimated functional mappings allow the adopted multi-objective BO
technique to explore the material search space and find the optimal set
of solutions. Among them, one specific solution using plastic as the
precursor material was selected for its ease of availability and was
experimentally validated. The results imply that under controlled
pyrolysis with KOH activation at 700 degrees C and moderate dwell time
(similar to 1 h), these feed stocks can yield carbons with exceptionally
high microporosity (>1.2 cm(3) g(-1)) and surface areas above 1150 m(2)
g(-1). This study underscores the role of symbolic approximation and
multi-objective optimization in navigating complex material design
space, enabling rapid evidence-based recommendations for sustainable
precursors, and accelerating the rational design of high-performance
carbon architectures for electrochemical energy storage systems. - FNClarivate Analytics Web of Science
- VR1.0
- PTJ
- AFBrindha Ramasubramanian
Rajdeep Dutta
Maciej Koperski
Vijila Chellappan
J Senthilnath
- TIMulti-property optimization for designing carbon electrodes
- SOJOURNAL OF POWER SOURCES
- DTArticle
- ABIn this paper, we propose a novel approach termed as Multi-Property
Optimization of Estimated Symbolic Expressions (MPOESE) to
systematically optimize carbon electrode properties using a dataset
comprising 300 data points compiled from the literature spanning from
2005 to 2025. The dataset captures key input parameters, including
precursor type, synthesis method, activation temperature, process time,
activation agents, and atmospheric conditions alongside output
parameters such as specific surface area, pore volume, and particle
size. The proposed approach, MPOESE, leverages the strengths of symbolic
regression (SR) to estimate mathematical expressions of multiple outputs
and Bayesian Optimization (BO) to determine their optimal values. Using
limited data available in the literature, MPOESE estimates nonlinear
relations and multivariate dependencies between the variable synthesis
conditions that are not readily discernible through traditional
trial-and-error experimentation or statistical regression. These
estimated functional mappings allow the adopted multi-objective BO
technique to explore the material search space and find the optimal set
of solutions. Among them, one specific solution using plastic as the
precursor material was selected for its ease of availability and was
experimentally validated. The results imply that under controlled
pyrolysis with KOH activation at 700 degrees C and moderate dwell time
(similar to 1 h), these feed stocks can yield carbons with exceptionally
high microporosity (>1.2 cm(3) g(-1)) and surface areas above 1150 m(2)
g(-1). This study underscores the role of symbolic approximation and
multi-objective optimization in navigating complex material design
space, enabling rapid evidence-based recommendations for sustainable
precursors, and accelerating the rational design of high-performance
carbon architectures for electrochemical energy storage systems. - Z90
- PUELSEVIER
- PARADARWEG 29, 1043 NX AMSTERDAM, NETHERLANDS
- SN0378-7753
- VL676
- DI10.1016/j.jpowsour.2026.239872
- UTWOS:001730079900001
- ER
- EF
|
Litvinov, Dmitrii; Gavriliuc, Virgil; Grzeszczyk, Magdalena; Vaklinova, Kristina; Watanabe, Kenji; Taniguchi, Takashi; Novoselov, Kostya S; Koperski, Maciej Surface defects in carbon-doped hexagonal boron nitride for
negative-contrast direct laser writing 2D MATERIALS, 13 (2), 2026, DOI: 10.1088/2053-1583/ae463c. Abstract | BibTeX | Endnote @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}
}
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. - FNClarivate Analytics Web of Science
- VR1.0
- PTJ
- AFDmitrii Litvinov
Virgil Gavriliuc
Magdalena Grzeszczyk
Kristina Vaklinova
Kenji Watanabe
Takashi Taniguchi
Kostya S Novoselov
Maciej Koperski
- TISurface defects in carbon-doped hexagonal boron nitride for
negative-contrast direct laser writing - SO2D MATERIALS
- DTArticle
- ABRadiative 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. - Z90
- PUIOP Publishing Ltd
- PANo.2 The Distillery, Glassfields, Avon Street, Bristol, ENGLAND
- SN2053-1583
- VL13
- DI10.1088/2053-1583/ae463c
- UTWOS:001701838600001
- ER
- EF
|
Jana, Dipankar; Soll, Aljoscha; Sofer, Zdenek; Orlita, Milan; Faugeras, Clement; Koperski, Maciej; Potemski, Marek Spin-Flip Optical Excitations in van der Waals Antiferromagnet
CrPS4 NANO LETTERS, 2026, DOI: 10.1021/acs.nanolett.6c01101. Abstract | BibTeX | Endnote @article{WOS:001792718100001,
title = {Spin-Flip Optical Excitations in van der Waals Antiferromagnet
CrPS4},
author = {Dipankar Jana and Aljoscha Soll and Zdenek Sofer and Milan Orlita and Clement Faugeras and Maciej Koperski and Marek Potemski},
doi = {10.1021/acs.nanolett.6c01101},
times_cited = {0},
issn = {1530-6984},
year = {2026},
date = {2026-06-01},
journal = {NANO LETTERS},
publisher = {AMER CHEMICAL SOC},
address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA},
abstract = {We investigate the near-infrared optical response of the semiconducting
van der Waals antiferromagnet CrPS4 and identify previously unreported
spin-entangled optical resonances. The strong and anisotropic
magnetic-field dependence of these resonances reflects the underlying
magnetic order and confirms the biaxial antiferromagnetic nature of
CrPS4. From the magnetic field evolution of the optical transition, we
extract key magnetic parameters, including the spin-flop ( approximate
to 0.9 T) and spin-saturation ( approximate to 8 T) fields. These
results demonstrate a potential pathway for all-optical probing of spin
states in van der Waals antiferromagnets, with relevance for
spin-sensitive optoelectronic and magneto-optical devices.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We investigate the near-infrared optical response of the semiconducting
van der Waals antiferromagnet CrPS4 and identify previously unreported
spin-entangled optical resonances. The strong and anisotropic
magnetic-field dependence of these resonances reflects the underlying
magnetic order and confirms the biaxial antiferromagnetic nature of
CrPS4. From the magnetic field evolution of the optical transition, we
extract key magnetic parameters, including the spin-flop ( approximate
to 0.9 T) and spin-saturation ( approximate to 8 T) fields. These
results demonstrate a potential pathway for all-optical probing of spin
states in van der Waals antiferromagnets, with relevance for
spin-sensitive optoelectronic and magneto-optical devices. - FNClarivate Analytics Web of Science
- VR1.0
- PTJ
- AFDipankar Jana
Aljoscha Soll
Zdenek Sofer
Milan Orlita
Clement Faugeras
Maciej Koperski
Marek Potemski
- TISpin-Flip Optical Excitations in van der Waals Antiferromagnet
CrPS4 - SONANO LETTERS
- DTArticle
- ABWe investigate the near-infrared optical response of the semiconducting
van der Waals antiferromagnet CrPS4 and identify previously unreported
spin-entangled optical resonances. The strong and anisotropic
magnetic-field dependence of these resonances reflects the underlying
magnetic order and confirms the biaxial antiferromagnetic nature of
CrPS4. From the magnetic field evolution of the optical transition, we
extract key magnetic parameters, including the spin-flop ( approximate
to 0.9 T) and spin-saturation ( approximate to 8 T) fields. These
results demonstrate a potential pathway for all-optical probing of spin
states in van der Waals antiferromagnets, with relevance for
spin-sensitive optoelectronic and magneto-optical devices. - Z90
- PUAMER CHEMICAL SOC
- PA1155 16TH ST, NW, WASHINGTON, DC 20036 USA
- SN1530-6984
- DI10.1021/acs.nanolett.6c01101
- UTWOS:001792718100001
- ER
- EF
|
Chen, Mingjun; Ho, Yi Wei; Lai, MingRui; Chen, Yuan; Sun, Xingjian; Kwok, Yuk Lam; Taniguchi, Takashi; Watanabe, Kenji; Koperski, Maciej; Quek, Su Ying; Eda, Goki Excitonic Shift Current in Monolayer MoS2 ACS NANO, 20 (23), pp. 16665-16674, 2026, DOI: 10.1021/acsnano.6c01332. Abstract | BibTeX | Endnote @article{WOS:001783592600001,
title = {Excitonic Shift Current in Monolayer MoS2},
author = {Mingjun Chen and Yi Wei Ho and MingRui Lai and Yuan Chen and Xingjian Sun and Yuk Lam Kwok and Takashi Taniguchi and Kenji Watanabe and Maciej Koperski and Su Ying Quek and Goki Eda},
doi = {10.1021/acsnano.6c01332},
times_cited = {0},
issn = {1936-0851},
year = {2026},
date = {2026-06-01},
journal = {ACS NANO},
volume = {20},
number = {23},
pages = {16665-16674},
publisher = {AMER CHEMICAL SOC},
address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA},
abstract = {In excitonic systems, where the relative motion of electrons and holes
is constrained by Coulomb interaction, how exciton effects influence the
magnitude of shift current-a phase-coherent shift of photoexcited Bloch
electrons and holes found in noncentrosymmetric materials-has been a
subject of ongoing theoretical interest. Here, we report observation of
exciton-enhanced shift current in uniaxially strained monolayer MoS2. We
obtain energy-dependent shift current conductivity tensor elements by
measuring polarization-resolved photocurrent spectrum in multiterminal
configurations, revealing a series of features that are absent in the
linear optical spectra. We show that these features can be attributed to
higher-order excitons and that their large shift vector plays an
important role in their observation. We further demonstrate that
electrostatic gating can modulate the shift current by two orders of
magnitude in a nonmonotonous manner, revealing the interplay between
free carrier conductivity and exciton oscillator strength.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In excitonic systems, where the relative motion of electrons and holes
is constrained by Coulomb interaction, how exciton effects influence the
magnitude of shift current-a phase-coherent shift of photoexcited Bloch
electrons and holes found in noncentrosymmetric materials-has been a
subject of ongoing theoretical interest. Here, we report observation of
exciton-enhanced shift current in uniaxially strained monolayer MoS2. We
obtain energy-dependent shift current conductivity tensor elements by
measuring polarization-resolved photocurrent spectrum in multiterminal
configurations, revealing a series of features that are absent in the
linear optical spectra. We show that these features can be attributed to
higher-order excitons and that their large shift vector plays an
important role in their observation. We further demonstrate that
electrostatic gating can modulate the shift current by two orders of
magnitude in a nonmonotonous manner, revealing the interplay between
free carrier conductivity and exciton oscillator strength. - FNClarivate Analytics Web of Science
- VR1.0
- PTJ
- AFMingjun Chen
Yi Wei Ho
MingRui Lai
Yuan Chen
Xingjian Sun
Yuk Lam Kwok
Takashi Taniguchi
Kenji Watanabe
Maciej Koperski
Su Ying Quek
Goki Eda
- TIExcitonic Shift Current in Monolayer MoS2
- SOACS NANO
- DTArticle
- ABIn excitonic systems, where the relative motion of electrons and holes
is constrained by Coulomb interaction, how exciton effects influence the
magnitude of shift current-a phase-coherent shift of photoexcited Bloch
electrons and holes found in noncentrosymmetric materials-has been a
subject of ongoing theoretical interest. Here, we report observation of
exciton-enhanced shift current in uniaxially strained monolayer MoS2. We
obtain energy-dependent shift current conductivity tensor elements by
measuring polarization-resolved photocurrent spectrum in multiterminal
configurations, revealing a series of features that are absent in the
linear optical spectra. We show that these features can be attributed to
higher-order excitons and that their large shift vector plays an
important role in their observation. We further demonstrate that
electrostatic gating can modulate the shift current by two orders of
magnitude in a nonmonotonous manner, revealing the interplay between
free carrier conductivity and exciton oscillator strength. - Z90
- PUAMER CHEMICAL SOC
- PA1155 16TH ST, NW, WASHINGTON, DC 20036 USA
- SN1936-0851
- VL20
- BP16665
- EP16674
- DI10.1021/acsnano.6c01332
- UTWOS:001783592600001
- ER
- EF
|
