Anomalous isotope effect on the optical bandgap in a monolayer transition metal dichalcogenide semiconductor

Yiling Yu; Volodymyr Turkowski; Jordan A. Hachtel; Alexander A. Puretzky; Anton V. Ievlev; Naseem U. Din; Sumner B. Harris; Vasudevan Iyer; Christopher M. Rouleau; Talat S. Rahman; David B. Geohegan; Kai Xiao

doi:10.1126/sciadv.adj0758

Anomalous isotope effect on the optical bandgap in a monolayer transition metal dichalcogenide semiconductor

Yiling Yu, Volodymyr Turkowski, Jordan A. Hachtel, Alexander A. Puretzky, Anton V. Ievlev, Naseem U. Din, Sumner B. Harris, Vasudevan Iyer, Christopher M. Rouleau, Talat S. Rahman, David B. Geohegan, Kai Xiao

Research output: Contribution to journal › Article › peer-review

2 Scopus citations

Abstract

Isotope effects have received increasing attention in materials science and engineering because altering isotopes directly affects phonons, which can affect both thermal properties and optoelectronic properties of conventional semiconductors. However, how isotopic mass affects the optoelectronic properties in 2D semiconductors remains unclear because of measurement uncertainties resulting from sample heterogeneities. Here, we report an anomalous optical bandgap energy red shift of 13 (±7) milli–electron volts as mass of Mo isotopes is increased in laterally structured ¹⁰⁰MoS₂-⁹²MoS₂ monolayers grown by a two-step chemical vapor deposition that mitigates the effects of heterogeneities. This trend, which is opposite to that observed in conventional semiconductors, is explained by many-body perturbation and time-dependent density functional theories that reveal unusually large exciton binding energy renormalizations exceeding the ground-state renormalization energy due to strong coupling between confined excitons and phonons. The isotope effect on the optical bandgap reported here provides perspective on the important role of exciton-phonon coupling in the physical properties of two-dimensional materials.

Original language	English
Article number	eadj0758
Journal	Science Advances
Volume	10
Issue number	8
DOIs	https://doi.org/10.1126/sciadv.adj0758
State	Published - Feb 2024

Funding

This work was supported by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division and was performed at the Center for Nanophase Materials Sciences (CNMS), Oak Ridge National Laboratory (ORNL). ToF-SIMS, STEM, and optical spectroscopy measurements were supported by the ORNL’s Center for Nanophase Materials Sciences, a U.S. DOE, Office of Science User Facility. The ToF-SIMS within ORNL’s Materials Characterization Core was provided by UT-Battelle, LLC under contract no. DE-AC05-00OR22725 with the U.S. DOE. Theoretical calculations were supported by U.S. DOE grant DE-FG02-07ER46354. Y.Y. acknowledges partial support by the National Natural Science Foundation of China (62204176) and the Fundamental Research Funds for the Central Universities (2042022kf1061).

Funders	Funder number
ORNL’s Center for Nanophase Materials Sciences
U.S. Department of Energy	DE-FG02-07ER46354
Office of Science
Basic Energy Sciences
Oak Ridge National Laboratory
UT-Battelle	DE-AC05-00OR22725
National Natural Science Foundation of China	62204176
Fundamental Research Funds for the Central Universities	2042022kf1061

Access to Document

10.1126/sciadv.adj0758

Cite this

@article{718a375a46e5438cb99f54bda96f54fd,

title = "Anomalous isotope effect on the optical bandgap in a monolayer transition metal dichalcogenide semiconductor",

abstract = "Isotope effects have received increasing attention in materials science and engineering because altering isotopes directly affects phonons, which can affect both thermal properties and optoelectronic properties of conventional semiconductors. However, how isotopic mass affects the optoelectronic properties in 2D semiconductors remains unclear because of measurement uncertainties resulting from sample heterogeneities. Here, we report an anomalous optical bandgap energy red shift of 13 (±7) milli–electron volts as mass of Mo isotopes is increased in laterally structured 100MoS2-92MoS2 monolayers grown by a two-step chemical vapor deposition that mitigates the effects of heterogeneities. This trend, which is opposite to that observed in conventional semiconductors, is explained by many-body perturbation and time-dependent density functional theories that reveal unusually large exciton binding energy renormalizations exceeding the ground-state renormalization energy due to strong coupling between confined excitons and phonons. The isotope effect on the optical bandgap reported here provides perspective on the important role of exciton-phonon coupling in the physical properties of two-dimensional materials.",

author = "Yiling Yu and Volodymyr Turkowski and Hachtel, {Jordan A.} and Puretzky, {Alexander A.} and Ievlev, {Anton V.} and Din, {Naseem U.} and Harris, {Sumner B.} and Vasudevan Iyer and Rouleau, {Christopher M.} and Rahman, {Talat S.} and Geohegan, {David B.} and Kai Xiao",

note = "Publisher Copyright: Copyright {\textcopyright} 2024 the Authors, some rights reserved.",

year = "2024",

month = feb,

doi = "10.1126/sciadv.adj0758",

language = "English",

volume = "10",

journal = "Science Advances",

issn = "2375-2548",

publisher = "American Association for the Advancement of Science",

number = "8",

}

TY - JOUR

T1 - Anomalous isotope effect on the optical bandgap in a monolayer transition metal dichalcogenide semiconductor

AU - Yu, Yiling

AU - Turkowski, Volodymyr

AU - Hachtel, Jordan A.

AU - Puretzky, Alexander A.

AU - Ievlev, Anton V.

AU - Din, Naseem U.

AU - Harris, Sumner B.

AU - Iyer, Vasudevan

AU - Rouleau, Christopher M.

AU - Rahman, Talat S.

AU - Geohegan, David B.

AU - Xiao, Kai

PY - 2024/2

Y1 - 2024/2

N2 - Isotope effects have received increasing attention in materials science and engineering because altering isotopes directly affects phonons, which can affect both thermal properties and optoelectronic properties of conventional semiconductors. However, how isotopic mass affects the optoelectronic properties in 2D semiconductors remains unclear because of measurement uncertainties resulting from sample heterogeneities. Here, we report an anomalous optical bandgap energy red shift of 13 (±7) milli–electron volts as mass of Mo isotopes is increased in laterally structured 100MoS2-92MoS2 monolayers grown by a two-step chemical vapor deposition that mitigates the effects of heterogeneities. This trend, which is opposite to that observed in conventional semiconductors, is explained by many-body perturbation and time-dependent density functional theories that reveal unusually large exciton binding energy renormalizations exceeding the ground-state renormalization energy due to strong coupling between confined excitons and phonons. The isotope effect on the optical bandgap reported here provides perspective on the important role of exciton-phonon coupling in the physical properties of two-dimensional materials.

AB - Isotope effects have received increasing attention in materials science and engineering because altering isotopes directly affects phonons, which can affect both thermal properties and optoelectronic properties of conventional semiconductors. However, how isotopic mass affects the optoelectronic properties in 2D semiconductors remains unclear because of measurement uncertainties resulting from sample heterogeneities. Here, we report an anomalous optical bandgap energy red shift of 13 (±7) milli–electron volts as mass of Mo isotopes is increased in laterally structured 100MoS2-92MoS2 monolayers grown by a two-step chemical vapor deposition that mitigates the effects of heterogeneities. This trend, which is opposite to that observed in conventional semiconductors, is explained by many-body perturbation and time-dependent density functional theories that reveal unusually large exciton binding energy renormalizations exceeding the ground-state renormalization energy due to strong coupling between confined excitons and phonons. The isotope effect on the optical bandgap reported here provides perspective on the important role of exciton-phonon coupling in the physical properties of two-dimensional materials.

UR - http://www.scopus.com/inward/record.url?scp=85185621112&partnerID=8YFLogxK

U2 - 10.1126/sciadv.adj0758

DO - 10.1126/sciadv.adj0758

M3 - Article

C2 - 38381831

AN - SCOPUS:85185621112

SN - 2375-2548

VL - 10

JO - Science Advances

JF - Science Advances

IS - 8

M1 - eadj0758

ER -

Anomalous isotope effect on the optical bandgap in a monolayer transition metal dichalcogenide semiconductor

Abstract

Funding

Access to Document

Other files and links

Fingerprint

Cite this