Article
Chemistry, Physical
Mukhtar Lawan Adam, Hongen Zhu, Zhanfeng Liu, Shengtao Cui, Pengjun Zhang, Yi Liu, Guobin Zhang, Xiaojun Wu, Zhe Sun, Li Song
Summary: By intercalating Sn atoms, the CDW phase in 1T-TiSe2 single crystals can be gradually suppressed, inducing charge doping and modulating the intrinsic electronic properties. Temperature-dependent ARPES results reveal the role of exciton-phonon interaction and the Jahn-Teller mechanism in the formation of CDW in this material.
Article
Chemistry, Multidisciplinary
Harshvardhan Jog, Luminita Harnagea, Dibyata Rout, Takashi Taniguchi, Kenji Watanabe, Eugene J. Mele, Ritesh Agarwal
Summary: We investigate the symmetries of 1T-TiSe2 and observe that the ground state of the CDW phase is achiral, but it can be transformed into a non-equilibrium chiral phase under high-intensity laser excitation, altering the electronic correlations in the material. The photogalvanic technique demonstrates the sensitivity to structural symmetries and provides evidence of different optically driven phases in 1T-TiSe2.
Article
Physics, Multidisciplinary
Q. Hu, J. Y. Liu, Q. Shi, F. J. Zhang, Y. Zhong, L. Lei, R. Ang
Summary: Understanding the interplay between superconductivity and charge-density wave (CDW) in transition-metal dichalcogenides (TMDs) is of fundamental interest in scientific research and applications. This study investigated the physical mechanism of superconducting transition in Ta-doped 1T-Ti1-xTaxSe2 single crystals through density functional theory (DFT) calculations and experiments. The results suggest that CDW suppression and enhancement of density of states near the Fermi level contribute to the emergence of superconductivity within the CDW phase, offering insights for potential electronic device applications.
Article
Materials Science, Multidisciplinary
Turgut Yilmaz, Elio Vescovo
Summary: Low-temperature, high-resolution angle resolved photoemission experiments on bulk 1T-TiSe2 samples reveal conspicuous band folding as the only prominent signature of the periodic lattice distortion. No confirmation of a bulk electronic gap supporting a charge density wave phase is found in light of the new data. These observations cast serious doubts on the common belief of an electronic instability as the likely origin for the observed structural transition in TiSe2.
Article
Chemistry, Physical
Zhao-Liang Wang, Guofu Chen, Xiaoliang Zhang, Dawei Tang
Summary: The study uses first-principles density functional theory and the phonon Boltzmann transport equation to investigate phonon transport characteristics in 1T-TiSe2. Results show that TiSe2 has extremely low lattice thermal conductivity, primarily attributed to acoustic phonons and a small portion of optical phonons, with the thermal conductivity decreasing as sample size shrinks. The high scattering rate and low group velocity result in the low thermal conductivity of the optical phonon mode in TiSe2.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Physics, Multidisciplinary
Li Zhu, Wei-Min Zhao, Zhen-Yu Jia, Huiping Li, Xuedong Xie, Qi-Yuan Li, Qi-Wei Wang, Li-Guo Dou, Ju-Gang Hu, Yi Zhang, Wenguang Zhu, Shun-Li Yu, Jian-Xin Li, Shao-Chun Li
Summary: Excitons in solid state are bosons generated by electron-hole pairs as the Coulomb screening is reduced. The condensation of excitons can lead to exotic physics like superfluidity and insulating state. 1T-TiSe2 in charge density wave (CDW) state is a candidate for exciton condensation, but it is still challenging to envision its excitonic effect in the two-dimensional limit applicable to future devices. In this study, we create a 2D epitaxial bilayer of 1T-TiSe2 to explore the exciton-associated effect and discover an unexpected state below the conduction band and within the CDW gap region, which is found to be in good agreement with the electron-exciton coupling through theoretical analysis. Our research provides a material platform for investigating exciton-based electronics and opto-electronics.
CHINESE PHYSICS LETTERS
(2023)
Article
Physics, Multidisciplinary
Shin-Ming Huang, Su-Yang Xu, Bahadur Singh, Ming-Chien Hsu, Chuang-Han Hsu, Chenliang Su, Arun Bansil, Hsin Lin
Summary: By using first-principles computations within the framework of density functional theory, this study reveals the connection between the symmetries of normal and CDW states and the electronic structure of 1T-TiSe2, emphasizing the crucial role of irreducible representations of electronic states and band gaps in driving the formation of CDW. The research demonstrates how symmetry-related topology can be directly obtained from the electronic structure, providing a practical pathway in the search for topological CDW insulators.
NEW JOURNAL OF PHYSICS
(2021)
Article
Physics, Multidisciplinary
Ming-Chien Hsu, Bahadur Singh, Chuang-Han Hsu, Su-Yang Xu, Hsin Lin, Shin-Ming Huang
Summary: CDW can change the symmetry and electronic structure of a system, leading to possible band inversion and offering a chance for topological phase transition. Monolayer 1T-TiSe2 was found to exhibit an unconventional CDW phase with a triple-q M-1(-) structure, which also results in a small M-1(+) CDW.
NEW JOURNAL OF PHYSICS
(2021)
Article
Physics, Multidisciplinary
Khalid M. Siddiqui, Daniel B. Durham, Frederick Cropp, Colin Ophus, Sangeeta Rajpurohit, Yanglin Zhu, Johan D. Carlstrom, Camille Stavrakas, Zhiqiang Mao, Archana Raja, Pietro Musumeci, Liang Z. Tan, Andrew M. Minor, Daniele Filippetto, Robert A. Kaindl
Summary: The study investigates the ultrafast structural dynamics of TaTe2, revealing a unique superstructure of trimer clusters that undergo melting and recovery processes on picosecond time scales.
COMMUNICATIONS PHYSICS
(2021)
Article
Chemistry, Physical
Atsushi Nomura, Tohru Kurosawa, Migaku Oda, Satoshi Demura, Shogo Kuwahara, Sora Kobayashi, Hideaki Sakata
Summary: The study investigates the tunneling spectra of 1T-TiSe2 in the CDW state and the dip structure below the Fermi level, aiming to determine whether this dip is a CDW gap. The answer to this question is crucial for understanding the driving mechanism of CDW.
Article
Materials Science, Multidisciplinary
Tanusree Saha, Arindam Pramanik, Barbara Ressel, Alessandra Ciavardini, Fabio Frassetto, Federico Galdenzi, Luca Poletto, Arun Ravindran, Primoz Rebernik Ribic, Giovanni De Ninno
Summary: This study investigates the photoinduced transient phase and ground state recovery dynamics in the complex material 1T-TaS2 using femtosecond time- and angle-resolved photoemission spectroscopy. The results reveal similarities between the band structures of the transient and equilibrium phases, with evidence for coexistence of the Mott insulating and metallic phases. The study also finds that the recoveries of Mott and CDW orders begin simultaneously, highlighting their coupling. Additionally, a metastable phase is observed during the recovery process, which is driven by the CDW lattice order.
Article
Chemistry, Physical
Wei-Min Zhao, Li Zhu, Zhengwei Nie, Qi-Yuan Li, Qi-Wei Wang, Li-Guo Dou, Ju-Gang Hu, Lede Xian, Sheng Meng, Shao-Chun Li
Summary: The study reveals that moire patterns formed at specific twist angles can trap charge density wave (CDW) states, which persist at room temperature, indicating potential applications in CDW-based technologies.
Article
Physics, Multidisciplinary
Chenhaoping Wen, Jingjing Gao, Yuan Xie, Qing Zhang, Pengfei Kong, Jinghui Wang, Yilan Jiang, Xuan Luo, Jun Li, Wenjian Lu, Yu-Ping Sun, Shichao Yan
Summary: Through low-temperature scanning tunneling microscopy and spectroscopy, we have revealed the different roles of narrow electronic bands in 1T-TaS2 and 4H(b)-TaS2 materials. The weak electronic hybridization between the 1T-TaS2 and 1H-TaS2 layers in 4H(b)-TaS2 shifts the narrow electronic band slightly above the Fermi level, suppressing the electronic correlation-induced band splitting, while the insulating gap in bulk 1T-TaS2 results from the overlap of narrow electronic bands in dimerized 1T-TaS2 layers.
PHYSICAL REVIEW LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Paulina Majchrzak, Sahar Pakdel, Deepnarayan Biswas, Alfred J. H. Jones, Klara Volckaert, Igor Markovic, Federico Andreatta, Raman Sankar, Chris Jozwiak, Eli Rotenberg, Aaron Bostwick, Charlotte E. Sanders, Yu Zhang, Gabriel Karras, Richard T. Chapman, Adam Wyatt, Emma Springate, Jill A. Miwa, Philip Hofmann, Phil D. C. King, Nicola Lanata, Young Jun Chang, Soren Ulstrup
Summary: Researchers perturb the electronic and vibrational states in a three-dimensional charge density wave material using an intense infrared laser pulse, and observe the light-induced hot carrier dynamics utilizing time- and angle-resolved photoemission spectroscopy. They find that the presence of hot carriers alters the phonon dispersion and leads to a new quasi-equilibrium state.
Article
Physics, Applied
Atsushi Nomura, Satoshi Demura, Shun Ohta, Sora Kobayashi, Hideaki Sakata
Summary: The temperature dependence of resistance in thinned samples of a layered transition metal dichalcogenide 1T-TiSe2 was measured. A thermal hysteresis of resistance was discovered, with the onset temperature being the same as the charge density wave transition temperature. The hysteresis was found to be related to both the temperature below and above the transition temperature.
JOURNAL OF LOW TEMPERATURE PHYSICS
(2023)
Article
Chemistry, Physical
Lili Han, Hao Cheng, Wei Liu, Haoqiang Li, Pengfei Ou, Ruoqian Lin, Hsiao-Tsu Wang, Chih-Wen Pao, Ashley R. Head, Chia-Hsin Wang, Xiao Tong, Cheng-Jun Sun, Way-Faung Pong, Jun Luo, Jin-Cheng Zheng, Huolin L. Xin
Summary: Single-atom catalysts have shown enhanced catalytic properties, but most studies have focused on a limited number of metal combinations. In this research, a library of 37 different monometallic elements is synthesized, characterized, and analyzed to establish the largest reported single-atom catalyst library. Unified principles on the design of single-atom catalysts are uncovered, and the library is utilized to explore complex multimetallic phase spaces. The findings demonstrate that single-atom anchor sites can serve as structural units to assemble concentration-complex single-atom catalyst materials with multiple elements.
Article
Nanoscience & Nanotechnology
Daniel J. Trainer, Jouko Nieminen, Fabrizio Bobba, Baokai Wang, Xiaoxing Xi, Arun Bansil, Maria Iavarone
Summary: In this study, the authors investigated common point defects in monolayer MoS2 using low-temperature scanning tunneling microscopy and spectroscopy. They identified the defects as molybdenum vacancies based on their characteristic in-gap resonances. The study also revealed the role of the substrate in the band structure of defective MoS2 monolayers.
NPJ 2D MATERIALS AND APPLICATIONS
(2022)
Article
Multidisciplinary Sciences
Jin-Cheng Zheng
Summary: This study systematically investigates the shape effects of transport distribution function on the thermoelectric properties of materials, and finds that the asymmetry of TDF can be used to universally describe the trend of thermoelectric properties. By defining symmetric and asymmetric TDF functions, a novel skewness is proposed for thermoelectric applications. The proposed thermoelectric skewness is able to accurately predict the thermoelectric power.
Article
Materials Science, Multidisciplinary
Mingjie Xu, Kongtao Chen, Fan Cao, Leonardo Velasco, Thomas M. Kaufman, Fan Ye, Horst Hahn, Jian Han, David J. Srolovitz, Xiaoqing Pan
Summary: This study presents the mechanism of grain boundary motion in polycrystalline materials through novel observations, simulations, and disconnection theory. The results show that the motion of grain boundaries is coupled through disconnection motion/reactions at grain boundary triple junctions. The driving force for migration affects the mode selection, with different modes observed under chemical potential jump and stress-driven conditions.
Article
Materials Science, Multidisciplinary
Larissa M. Woryk, Sicong He, Emily M. Hopkins, Chang-Yu Hung, Jian Han, David J. Srolovitz, Jaime Marian, Mitra L. Taheri
Summary: A numerical methodology is presented to compute the Nye-tensor fingerprints of dislocation loop absorption at grain boundaries (GBs) and compare them with TEM observations. This approach connects atomistic simulations with experimentally extracted GND maps to facilitate the interpretation of damage processes. The method provides a framework for future investigations of defect absorption by grain boundaries under irradiation conditions.
PHYSICAL REVIEW MATERIALS
(2022)
Article
Chemistry, Physical
Wang Zhang, Fu-Ye Du, Yang Dai, Jin-Cheng Zheng
Summary: In this study, atomic simulations were conducted to investigate the effects of lattice strains on the Li+ ion migration energy barrier in olivine phosphates. It was found that biaxial tensile strain perpendicular to the migration path is most beneficial in reducing the energy barrier of Li+ ions. SL3 + 1 and SL1 + 3 were identified as the most favorable paths for Li+ ion migration. This work provides valuable insights for cathode materials and battery design.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Rui Wang, Xiaoxiao Ma, Linfeng Zhang, Han Wang, David J. Srolovitz, Tongqi Wen, Zhaoxuan Wu
Summary: This study focuses on the development of two interatomic potentials for BCC vanadium (V) using classical semiempirical modified embedded-atom method and the ML Deep Potential framework. Both potentials can reproduce various defect properties relevant to plastic deformation and fracture.
PHYSICAL REVIEW MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Caihao Qiu, Marco Salvalaglio, David J. Srolovitz, Jian Han
Summary: An intrinsic feature of crystalline systems is the presence of disconnections, which strongly affect the morphology and motion of interfaces. These elastic interactions modify equilibrium interface morphologies compared to surface energy and affect interface kinetics, leading to a faceting-defaceting transition.
Article
Physics, Applied
G. Berti, C. G. Torres-Castanedo, D. P. Goronzy, M. J. Bedzyk, M. C. Hersam, C. Kopas, J. Marshall, M. Iavarone
Summary: Niobium thin films are important for superconducting microwave resonators used in quantum systems. The understanding of loss mechanisms affecting the performance of superconducting devices is still limited. This study investigates the Nb/substrate interface by comparing the local superconducting properties of Nb films grown on hydrogen-passivated H:Si(111) substrates and typical Si(001) substrates. The results show that the Nb films grown on H:Si(111) substrates have a smoother and less defective interface, exhibiting more uniform superconducting properties and less quasiparticle broadening.
APPLIED PHYSICS LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Shuai Chen, Zachary H. Aitken, Subrahmanyam Pattamatta, Zhaoxuan Wu, Zhi Gen Yu, David J. Srolovitz, Peter K. Liaw, Yong-Wei Zhang
Summary: By employing density-functional theory calculations, Monte Carlo method, and molecular dynamic simulation, this study investigates the role of short-range ordering (SRO) on dislocation kinetics in a BCC MoTaTiWZr high-entropy alloy. The results demonstrate that SRO enhances the energy barriers for both edge and screw dislocation motion, giving rise to the dominance of edge dislocations in the BCC RHEA.
Article
Engineering, Mechanical
Tongqi Wen, Anwen Liu, Rui Wang, Linfeng Zhang, Jian Han, Han Wang, David J. Srolovitz, Zhaoxuan Wu
Summary: This study determines the properties of dislocation cores, twins, and cracks in HCP and BCC Ti using Deep Potential (DP), DFT, and linear elastic fracture mechanics. It provides insights into the behavior of slip dislocations and the brittleness of cracks on basal planes, as well as the energy and structure of twin boundaries. The results offer a comprehensive understanding of Ti plasticity and fracture.
INTERNATIONAL JOURNAL OF PLASTICITY
(2023)
Article
Multidisciplinary Sciences
Shuai Chen, Ping Liu, Qingxiang Pei, Zhi Gen Yu, Zachary H. Aitken, Wanghui Li, Zhaoxuan Wu, Rajarshi Banerjee, David J. Srolovitz, Peter K. Liaw, Yong-Wei Zhang
Summary: This study constructs nanolamellar high-entropy alloys and explores their mechanical properties using molecular dynamic simulation and density functional theory calculation. The results show that the nanolamellar structure exhibits ideal plastic behavior and remarkable shape memory effect, highlighting the importance of nanolamellar structures in controlling the mechanical and functional properties of high-entropy alloys.
Article
Chemistry, Multidisciplinary
Rongzhi Wang, Jin-Cheng Zheng
Summary: In this study, the catalytic performance of three types of pristine and decorated borophenes was investigated using first-principles calculations. Results show that Ni-doped alpha borophene exhibits high activity as a catalyst for water splitting. Doping or decorating with different transition metals has a significant impact on the catalytic performance of alpha, beta(12), and chi(3) borophenes. Ni-doped alpha borophene shows a low Gibbs free energy of hydrogen adsorption (ΔG(H) approximately 0.055 eV) for the hydrogen evolution reaction (HER) and promising overpotential (0.455 V) for the oxygen evolution reaction (OER). This study provides critical insights into the catalytic activity of borophene for water splitting by selecting suitable decorated metals.
Article
Quantum Science & Technology
Cheng-Lin Hong, Ting Tsai, Jyh-Pin Chou, Peng-Jen Chen, Pei-Kai Tsai, Yu-Cheng Chen, En-Jui Kuo, David Srolovitz, Alice Hu, Yuan-Chung Cheng, Hsi-Sheng Goan
Summary: Although quantum chemistry calculations on quantum computers are currently limited to small molecules, we propose a method using Daubechies wavelet functions that can achieve accurate and efficient quantum computations. Our method provides a better description of the molecular Hamiltonian and enables predictions that are in agreement with experimental measurements.
Article
Chemistry, Physical
Ning Wei, Yang Chen, Kun Cai, Yingyan Zhang, Qingxiang Pei, Jin-Cheng Zheng, Yiu-Wing Mai, Junhua Zhao
Summary: This study systematically investigated the effects of creases on the thermal properties of graphene origami using molecular dynamics simulations. The results showed that tensile strain reduces the interfacial thermal resistance due to the presence of creases. This finding has important implications for the design of next-generation thermal management devices and flexible electronics with tuneable properties.
GREEN ENERGY & ENVIRONMENT
(2022)
