Article
Chemistry, Multidisciplinary
Yang Xia, Joel Berry, Mikko P. Haataja
Summary: This paper introduces a new approach to control the phase of TMD monolayers by applying macroscopic in-plane strains, with the introduction of hole arrays identified as the most feasible phase programming route.
Article
Chemistry, Multidisciplinary
Jenny Hu, Leo Yu, Xueqi Chen, Wanhee Lee, C. Mathew Mate, Tony F. Heinz
Summary: This study investigates the transfer of strain in vertically stacked van-der-Waals heterostructures and finds that high strain transfer efficiency is observed in aligned heterostructures with small twist angles.
Article
Chemistry, Multidisciplinary
Zihao Huang, Guoyu Xian, Xiangbo Xiao, Xianghe Han, Guojian Qian, Chengmin Shen, Haitao Yang, Hui Chen, Banggui Liu, Ziqiang Wang, Hong-Jun Gao
Summary: Landau quantization in a strained type-II Dirac semimetal NiTe2 is studied using spectroscopic-imaging scanning tunneling microscopy. Single-sequence Landau levels originating from the quantization of topological surface state (TSS) are observed on uniform-height surfaces at a magnetic field. Multiple sequence of Landau levels appear in strained surface regions where the rotation symmetry is broken. First-principles calculations reveal that the multiple Landau levels are a result of the lifting of valley degeneracy of TSS by in-plane uniaxial or shear strains. This finding provides a pathway to tune the degrees of freedom and quantum numbers of TMDs for practical applications.
Article
Chemistry, Multidisciplinary
Alvaro Rodriguez, Javier Varillas, Golam Haider, Martin Kalbac, Otakar Frank
Summary: We investigate the intrinsic strain in twisted MoS2/MoSe2 heterobilayers and find that small twist angles result in atomic reconstructions, large moire periodicities, and high local strains. The formation of moire superlattices is assisted by stacking domain reconstructions, leading to a complex strain distribution. Larger twist angles hinder lattice reconstruction and result in moire patterns with small periodicities and negligible strains.
Review
Chemistry, Physical
Farabi Bozheyev
Summary: TMDs are extensively studied for electronic, photonic, and energy applications due to their suitable electronic structure for solar light absorption and simple exfoliation technique. Various designs and combinations of 2D single layers are explored to form heterojunctions and multijunctions for improved light absorption efficiency and charge carrier transfer.
CURRENT OPINION IN ELECTROCHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Di Zhang, Dawei Zhai, Sha Deng, Wang Yao, Qizhong Zhu
Summary: Excitons in monolayer transition metal dichalcogenide are entangled in both valley and orbital angular momentum when confined by a strain field. By tuning the trap profile and magnetic field, the exciton states can be engineered and used as polarization-OAM locked single photon emitters, which can also be entangled under certain conditions and highly tunable by strain trap and magnetic field. This proposal provides a novel scheme for generating polarization-OAM locked/entangled photons at the nanoscale, with high integrability and tunability, promising exciting opportunities for quantum information applications.
Article
Optics
Min-Soo Hwang, Hong-Gyu Park
Summary: Lithographically designed potential wells in monolayer WS2 microcavities can manipulate nonlinear transition-metal dichalcogenide polaritons and enhance the interaction strength between polaritons and the reservoir.
LIGHT-SCIENCE & APPLICATIONS
(2023)
Article
Nanoscience & Nanotechnology
Mingjie Pu, Wanlin Guo, Yufeng Guo
Summary: Using a combination of non-noble metal atoms and defect-engineered transition metal dichalcogenide (TMD) monolayers, new types of single-atom catalysts for electrochemical CO2RR can be designed, exhibiting better catalytic performance and selectivity. Applying suitable biaxial tensile strains on defect-engineered TMDs can significantly reduce the overpotentials of non-noble metal atoms, with the vacancy defects and charge transfer playing a crucial role in improving catalytic activity.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Nanoscience & Nanotechnology
Tomojit Chowdhury, Kiyoung Jo, Surendra B. Anantharaman, Todd H. Brintlinger, Deep Jariwala, Thomas J. Kempa
Summary: The study identified anomalous photoluminescence from nonplanar assemblies of 2D MoSe2 monolayers with silicon nanowires, suggesting a new excitonic state localized within a nanostrained region. The importance of nanoscale manipulation of strain in low-dimensional materials to control excitonic and other properties effectively was highlighted in this work.
Article
Optics
Battulga Munkhbat, Betul Kucukoz, Denis G. Baranov, Tomasz J. Antosiewicz, Timur O. Shegai
Summary: Transition metal dichalcogenides (TMDs), including semiconducting WS2, in-plane anisotropic ReS2, and metallic TaSe2, TaS2, and NbSe2, have attracted significant attention due to their exceptional optical, excitonic, mechanical, and electronic properties. Nanostructured multilayer TMDs, with their high refractive indices and optical anisotropy, show promise for nanophotonic applications. Advanced nanofabrication strategies, including careful selection of resists for electron beam lithography and etching methods, are discussed, with a specific focus on non-conductive substrates such as SiO2. These TMD-based nanostructures have the potential to impact high-index nanophotonics, plasmonics, and on-chip optical circuits.
LASER & PHOTONICS REVIEWS
(2023)
Article
Multidisciplinary Sciences
Elyse Barre, Ouri Karni, Erfu Liu, Aidan L. O'Beirne, Xueqi Chen, Henrique B. Ribeiro, Leo Yu, Bumho Kim, Kenji Watanabe, Takashi Taniguchi, Katayun Barmak, Chun Hung Lui, Sivan Refaely-Abramson, Felipe H. da Jornada, Tony F. Heinz
Summary: Interlayer excitons, electron-hole pairs bound across two monolayer van der Waals semiconductors, offer promising electrical tunability and localizability. The dielectric response of interlayer excitons was directly measured using their static electric dipole moment, and an intrinsic radiative lifetime and transition characteristics were determined. This study identifies a momentum-indirect emission mechanism and emphasizes the importance of characterizing absorption for applications relying on light-matter interactions.
Article
Physics, Applied
Shasha Li, Yong Yan, Jie Li, Mengdan Qian, Chenhai Shen, Xiaohui Song, Yurong Jiang, Congxin Xia, Jingbo Li
Summary: In this study, a new type of SWIR photodetector based on In2(1-x)Sb2xSe3 material was designed and prepared, and it showed excellent photoresponse performance, indicating its potential as an important material for SWIR photodetectors.
APPLIED PHYSICS LETTERS
(2022)
Article
Physics, Multidisciplinary
Sara Shabani, Dorri Halbertal, Wenjing Wu, Mingxing Chen, Song Liu, James Hone, Wang Yao, D. N. Basov, Xiaoyang Zhu, Abhay N. Pasupathy
Summary: In twisted bilayers of semiconducting transition metal dichalcogenides, the moire potential is unexpectedly large, reaching values above 300 meV and is a non-monotonic function of moire wavelength.
Article
Chemistry, Multidisciplinary
Yeonjeong Koo, Yongchul Kim, Soo Ho Choi, Hyeongwoo Lee, Jinseong Choi, Dong Yun Lee, Mingu Kang, Hyun Seok Lee, Ki Kang Kim, Geunsik Lee, Kyoung-Duck Park
Summary: This study demonstrates dynamic nano-mechanical strain-engineering of naturally-formed wrinkles in a WSe2 monolayer using hyperspectral adaptive tip-enhanced PL (a-TEPL) spectroscopy. The results show that by dynamically adjusting the wrinkles at the nanoscale, exciton dynamics and emission properties can be tuned reversibly. This provides a new strategy for robust, tunable, and ultracompact nano-optical sources in atomically thin semiconductors.
ADVANCED MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Yohei Yomogida, Mai Nagano, Zheng Liu, Kan Ueji, Md. Ashiqur Rahman, Abdul Ahad, Akane Ihara, Hiroyuki Nishidome, Takashi Yagi, Yusuke Nakanishi, Yasumitsu Miyata, Kazuhiro Yanagi
Summary: TMDC nanotubes are materials with unique physical properties, and controlling their structures is crucial for their scientific research and applications. This study successfully synthesized heterostructures of TMDC nanotubes and demonstrated a technique for controlling their features such as diameter, layer number, and crystallinity.
Article
Chemistry, Physical
A. Young Lee, Kihyuk Yang, Nguyen Duc Anh, Chulho Park, Seung Mi Lee, Tae Geol Lee, Mun Seok Jeong
Summary: The study investigates the relationship between the intensity ratio of D* to G band and the reduction of graphene oxide (GO) to evaluate the degree of reduction of rGO. Spectral analysis and systematic research revealed a strong linkage between the D*/G intensity ratio and the C/O atomic ratio, which provides an indicator of the quality of rGO for optimal performance in applications.
APPLIED SURFACE SCIENCE
(2021)
Article
Chemistry, Physical
Daehee Seol, Songkil Kim, Woo-Sung Jang, Yeongrok Jin, Seunghun Kang, Sera Kim, Dongyeun Won, Chanwoo Lee, Young-Min Kim, Jaekwang Lee, Heejun Yang, Mun Seok Jeong, Alex Belianinov, Alexander Tselev, Suhas Somnath, Christopher R. Smith, Olga S. Ovchinnikova, Nina Balke, Yunseok Kim
Summary: It has been demonstrated that focused ion beams can create out-of-plane piezoelectricity on multi-layered MoTe2, and the selectively patterned out-of-plane piezoelectricity in the desired area was quantitatively examined using atomic force microscopy. This approach is expected to expand the application fields of TMD-based devices.
Article
Chemistry, Physical
Tanzila Tasnim Ava, Hyeon Jun Jeong, Hyang Mi Yu, Kang-Nyeoung Lee, Tarek M. Abdel-Fattah, Mun Seok Jeong, Gon Namkoong
Summary: This study demonstrates that poly (methyl methacrylate) (PMMA) can enhance the thermal stability of perovskite films by altering the chemical composition of grain boundaries to make them more heat-resistant. Hydrated compounds act as catalysts for thermal degradation at grain boundaries, while PMMA absorbs moisture and drives it out, protecting the grain boundaries from degradation.
APPLIED SURFACE SCIENCE
(2021)
Article
Multidisciplinary Sciences
Dong Yun Lee, Chulho Park, Jinseong Choi, Yeonjeong Koo, Mingu Kang, Mun Seok Jeong, Markus B. Raschke, Kyoung-Duck Park
Summary: Adaptive tip-enhanced nano-spectroscopy optimizes the nano-optical vector-field at the tip apex through dynamic wavefront shaping, enabling additional signal enhancement and near-field polarization control.
NATURE COMMUNICATIONS
(2021)
Article
Materials Science, Multidisciplinary
Geunchang Choi, Tuan Khanh Chau, Sung Ju Hong, Dasom Kim, Sung Hyuk Kim, Dai-Sik Kim, Dongseok Suh, Young-Mi Bahk, Mun Seok Jeong
Summary: The study demonstrates a method for achieving negative-type high on/off ratio and ultrafast terahertz modulation using graphene/metal nanoslot antennas. The graphene covering and optical pumping result in resonant modulation of terahertz transmission. Rapid carrier relaxation induced by a strong terahertz field contributes to faster modulation of transient terahertz transmission.
ADVANCED OPTICAL MATERIALS
(2021)
Article
Chemistry, Physical
Junseok Jeong, Dae Kwon Jin, Joonghoon Choi, Junho Jang, Bong Kyun Kang, Qingxiao Wang, Won Il Park, Mun Seok Jeong, Byeong-Soo Bae, Woo Seok Yang, Moon J. Kim, Young Joon Hong
Summary: Remote epitaxy of GaN p-n homojunction microcrystals has been demonstrated for fabricating transferable, flexible white light-emitting diodes (WLEDs). The WLEDs show reliable performance even after repetitive bending and cycling temperature environments, making them suitable for flexible and modular light panels.
Article
Nanoscience & Nanotechnology
Gisung Kim, Namhee Kwon, Dongho Lee, Mijoung Kim, Moonhoe Kim, Yongjei Lee, WooJong Kim, Daseul Hyeon, Bora Kim, Mun Seok Jeong, Jinpyo Hong, JungYup Yang
Summary: Recent studies have found that copper (I) thiocyanate (CuSCN) has significant potential as a hole extraction material for perovskite solar cells. However, the use of CuSCN can lead to unwanted dissociation of MAPbI(3) to PbI2, and the solvent DES can damage the surface of the perovskite layer. By increasing the molar ratio of MAI in the MAPbI(3) precursor solution, the surface damage to MAPbI(3) can be reduced and the dissociation to PbI2 can be effectively suppressed.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Physical
Jaekak Yoo, Kihyuk Yang, Byeong Wook Cho, Ki Kang Kim, Seong Chu Lim, Seung Mi Lee, Mun Seok Jeong
Summary: In this study, the phonon vibrational origin of a single sulfur-vacancy-induced Raman peak was identified as A(1)'(k) through quantum mechanical calculations. This finding is of great importance for improving the quality of transition metal dichalcogenides materials.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
Byeong Geun Jeong, Chanwoo Lee, Sung Hyuk Kim, Seok Joon Yun, Dong Hyeon Kim, Juchan Lee, Dongki Lee, Ki Kang Kim, Seong Chu Lim, Mun Seok Jeong
Summary: Defect analysis in two-dimensional transition-metal dichalcogenides (TMDs) is important due to its significant impact on the optical and electrical properties of TMD. This study investigated the influence of sulfur vacancies and oxygen substitution on the optical properties of WS2 using laser irradiation technique. The defect-induced photoluminescence (PL) exhibited distinct features depending on the type of defects, resulting in changes in the intensities and peak positions of excitons, biexcitons, and defect-bound excitons. Defect-activated Raman modes provided information about the defects and revealed the origin of the alteration in PL.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Nanoscience & Nanotechnology
Bora Kim, Moonhoe Kim, Hyojung Kim, Sohee Jeong, JungYup Yang, Mun Seok Jeong
Summary: Perovskite solar cells (PSCs) have short lifetimes, but by using transition metal dichalcogenide (TMD) interlayers, both efficiency and stability of the devices can be improved.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Nanoscience & Nanotechnology
Phuong Huyen Nguyen, Duc Hieu Nguyen, Donghyoung Kim, Mun Kyoung Kim, Jiseong Jang, Woo Hyeong Sim, Hyung Mo Jeong, Gon Namkoong, Mun Seok Jeong
Summary: This study investigates the regeneration of oxidized titanium carbide (Ti3C2Tx) through hydrofluoric acid (HF) post-treatment. The research reveals that the post-treatment can restore the structure and surface composition of MXene nanosheets, thereby improving their electrical conductivity and prolonging their conductivity maintenance time. This finding is crucial for the rational design of Ti3C2Tx-based devices and functional coatings.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Nanoscience & Nanotechnology
Hwi Je Woo, Sangmin Ji, Jaewon Han, Seongwon Woo, Hyuntae Kim, Seonyeong Kim, Chang-Won Lee, Soobong Choi, Deok-Soo Kim, Mun Seok Jeong, Euyheon Hwang, Byungkwon Lim, Young Jae Song
Summary: We used scattering-type near-field scanning optical microscopy (s-NSOM) to observe optical phenomena on mono-crystalline silver nanoflakes. The momentum of tip-launched surface plasmon polaritons (SPPs) was successfully identified and showed good agreement with analytical calculations.
ACS APPLIED NANO MATERIALS
(2023)
Article
Engineering, Electrical & Electronic
Wonchae Jeong, Taeyoung Kim, Yoonsok Kim, Mun Seok Jeong, Eun Kyu Kim
Summary: We demonstrate area-selective doping of MoS2 field-effect transistors using 1,2-dichloroethane (DCE) solution. X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy measurements confirm the blocked layer (BL) using a photoresist, which suppresses the doping effect of the DCE treatment. Electrical measurements confirm the enhancement in field-effect mobility and subthreshold swing after area-selective doping.
SEMICONDUCTOR SCIENCE AND TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Geunchang Choi, Dong-Hwan Choi, Junho Ryeom, Dae Young, Wu-Sin Kim, Ju-Jin Kim, Young-Mi Bahk, Mun Seok Jeong
Summary: High-quality indium thin films were fabricated by substrate cooling method, reducing the threshold thickness for insulator-to-metal transition. The films' complex conductivities were measured by terahertz time-domain spectroscopy, showing that the conductivity of the cooled indium films was 10 times higher than that deposited at room temperature, despite their lower thickness. These results suggest the promising applications of substrate cooling in metal thin films and contacts.
CURRENT APPLIED PHYSICS
(2023)
Article
Automation & Control Systems
Jaekak Yoo, Youngwoo Cho, Byeonggeun Jeong, Soo Ho Choi, Ki Kang Kim, Seong Chu Lim, Seung Mi Lee, Jaegul Choo, Mun Seok Jeong
Summary: The application of explainable artificial intelligence in nanomaterial research has facilitated the discovery of novel physical findings. In this study, the correlation between light scattering and emission in a WSe2 monolayer is investigated by bridging explainable artificial intelligence and quantum mechanical calculations. Convolutional neural networks are trained using light scattering and emission data to determine the relationships between them. The findings are independently evaluated through quantum mechanical calculations, providing reliable fundamental physical insight and suggesting a novel methodology for materials science.
ADVANCED INTELLIGENT SYSTEMS
(2023)
