Article
Materials Science, Multidisciplinary
Pengbo Ding, Yifan Zhu, Zhijia Han, Long Li, Liang Zhang, Yuhang Cai, David J. Singh, Lenan Zhang, Wenqing Zhang, Sunmi Shin, Jiong Yang, Weishu Liu, Liang Guo
Summary: In this study, ultrafast spectroscopy of coherent acoustic phonons was used to characterize the ADP of thermoelectric materials, specifically Mg3Sb2. The method relies on the transient Coulombic interaction between carriers and acoustic phonons, and is free from other scattering channels. It is particularly feasible for studying thermoelectric materials due to their strong phonon anharmonicity and small band gaps, ensuring measurement accuracy.
Article
Chemistry, Physical
R. Abinaya, J. Archana, S. Harish, M. Navaneethan, C. Muthamizhchelvan, S. Ponnusamy, H. Udono, R. Sugahara, Y. Hayakawa, M. Shimomura
Summary: This study prepared ultrathin layered molybdenum disulphide (MoS2) nanosheets/PANI nanocomposites via a hydrothermal route, investigating the influence of PANI on thermoelectric properties. It was found that the insertion of PANI could enhance the potential difference of MoS2/ PANI nanocomposites, reduce thermal conductivity, and increase conductivity.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2021)
Article
Chemistry, Multidisciplinary
Li Wang, Shohei Takeda, Ryota Sato, Masanori Sakamoto, Toshiharu Teranishi, Naoto Tamai
Summary: This study investigates the coherent acoustic phonon vibrations of Au nanopolyhedrons under different conditions, revealing unique vibrational modes and displacement characteristics associated with each type of nanopolyhedron morphology. The findings suggest potential applications for morphology-controllable metal nanoresonators.
Article
Acoustics
Liang Zhang, Yuhang Cai, Long Li, Wenshuai Feng, Rui-Tao Wen, Sunmi Shin, Liang Guo
Summary: In this work, a novel ultrafast spectroscopy method is proposed to extract the acoustic deformation potential (ADP) coupling constant of a semiconductor by jointly analyzing the coherent acoustic phonon signals with and without a metal transducer. The ADP coupling constant corresponding to the bandgap of GaAs was successfully extracted using a pump photon energy near the bandgap, which agrees well with literature values. However, with a larger pump photon energy, the ADP coupling constant deviates from the one for the bandgap due to contributions from the carrier dynamics in multiple energy and wavevector states.
Article
Physics, Multidisciplinary
Shaoxiang Sheng, Anne-Catherine Oeter, Mohamad Abdo, Kurt Lichtenberg, Mario Hentschel, Sebastian Loth
Summary: Localized coherent acoustic phonon wave packets can be generated and manipulated in a scanning tunneling microscope using tip-enhanced terahertz electric fields, allowing for ultrafast control of solids. The lattice displacement can be precisely controlled by varying the tip-sample distance, enabling advanced terahertz engineering and exploration of coherent phonons at the atomic scale.
PHYSICAL REVIEW LETTERS
(2022)
Article
Chemistry, Physical
Bin Liu, Yangyu Guo, Vladimir I. Khvesyuk, Alexander A. Barinov, Moran Wang
Summary: This theoretical investigation explores coherent-to-incoherent heat conduction in multilayer nanostructures, demonstrating that in the coherent regime, accurate predictions can be made using the elastic continuum model. The study shows that as temperature or system size increases, phonon dephasing scattering results in deviation from coherent-limit calculation, and by introducing phonon incoherence, classical minimum thermal conductivity can be reproduced, extending the pure wave model into the wave-particle crossing regime.
Article
Multidisciplinary Sciences
E. Rongione, O. Gueckstock, M. Mattern, O. Gomonay, H. Meer, C. Schmitt, R. Ramos, T. Kikkawa, M. Micica, E. Saitoh, J. Sinova, H. Jaffres, J. Mangeney, S. T. B. Goennenwein, S. Gepraegs, T. Kampfrath, M. Klaeui, M. Bargheer, T. S. Seifert, S. Dhillon, R. Lebrun
Summary: This paper demonstrates the generation of both broadband and narrowband terahertz emission in NiO/Pt thin films. The researchers identify two excitation processes, one involving an off-resonant instantaneous optical spin torque and the other involving a strain-wave-induced terahertz torque. These findings contribute to the development of fast opto-spintronic devices based on antiferromagnetic materials.
NATURE COMMUNICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Long Li, Feng He, Xu Zhao, Zhen Tong, Liang Guo
Summary: This letter illustrates the importance of addressing the diffusion effect in acoustic deformation potential (ADP) characterization using ultrafast spectroscopy of coherent acoustic phonon (CAP) dynamics. It is found that in Ge, both the ADP mechanism and the thermoelastic effect have comparable contributions to CAP generation.
Article
Engineering, Electrical & Electronic
Hongyu Chen, Dongyang Chen, Ronghua Huan, Yongqing Fu, Jin Xie
Summary: This paper demonstrates the manipulation of coherent phonons using a single-mode circular electrostatic resonator, and verifies its mechanism for controlling phononic frequency comb parameters both experimentally and theoretically. The spacing of the phononic frequency comb system can be regulated solely by the pump frequency, achieving a spacing resolution of 0.1 Hz at room temperature. Feasibility of manipulating phonons using electrostatic resonators is verified through nonlinear modulation and damping loss experiments.
SENSORS AND ACTUATORS A-PHYSICAL
(2023)
Article
Physics, Multidisciplinary
Cheng-Xiang Zhao, Miao-Miao Zheng, Yuan Qie, Fang-Wei Han
Summary: In this study, the theoretical aspect of acoustic-phonon emission from monolayer molybdenum disulfide (ML-MoS2) under a direct-current electric field is investigated using the Boltzmann equation method. It is found that ML-MoS2 can generate terahertz acoustic-phonons through Cerenkov emission when subjected to a weak electric field. The emission mechanisms are analyzed from the perspective of condensed matter physics, and the results are compared with graphene and GaAs. The findings suggest that ML-MoS2 can complement the acoustic-phonon emission characteristics of graphene and GaAs and be used in tunable hypersonic devices such as terahertz sound sources.
Article
Chemistry, Physical
Petra Papez, Franci Merzel, Matej Praprotnik
Summary: The application of terahertz radiation affects protein structure and cellular function. By analyzing dynamic fluctuations and using molecular dynamics simulations, the study shows that proteins are highly susceptible to acoustic waves with frequencies corresponding to internal protein vibrations. The compactness of the protein structure and the breathing-like character of collective modes are observed to change under the influence of pressure waves.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Kaiqing Zhang, Yin Kang, Tao Liu, Zhen Wang, Chao Feng, Wencheng Fang, Zhentang Zhao
Summary: This work presents a compact accelerator-based light source for generating coherent THz radiation with high pulse energy and tunable frequency, opening up new opportunities for various scientific frontiers such as THz pump-probe and single-shot THz bioimaging.
APPLIED SCIENCES-BASEL
(2021)
Article
Chemistry, Inorganic & Nuclear
Tudor-Gabriel Mocioi, Antonia Ghita, Vasily V. V. Temnov
Summary: Using valid experimental parameters, this study quantifies the magnitude of resonantly phonon-driven precession of exchange magnons in freestanding ferromagnetic nickel thin films on their thickness L. Analytical solutions reveal a nonmonotonous dependence of the peak magnetization precession on the film thickness, attributed to different dependencies of multiple prefactors involved in the expression for the total magnetization dynamics. The magnetization precession can be amplified by a Q-factor of either the phonon or the magnon resonance, depending on the ratio of acoustic and magnetic damping constants.
Article
Physics, Applied
Mingxian Huang, Wenbin Hu, Huaiwu Zhang, Feiming Bai
Summary: Surface acoustic waves (SAWs) can transmit magnetization oscillation inside magnetoelastic films in the form of magnetoacoustic waves. If the frequency and wavenumber of SAWs match those of spin waves, magnon excitation can be observed. In this study, longitudinal leaky SAWs were found to be a very effective means to excite stronger phonon-magnon coupling than Rayleigh SAWs at a lower wavenumber.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Chemistry, Physical
Chang-Fu Huo, Rui Wen, Xiao-Qing Yan, De-Kang Li, Kai-Xuan Huang, Yizhi Zhu, Qiannan Cui, Chunxiang Xu, Zhi-Bo Liu, Jian-Guo Tian
Summary: The study investigates the photoexcited-carrier dynamics and coherent acoustic phonon oscillations in PdSe2 flakes of various thicknesses, revealing that the CAP frequency is thickness-dependent and the deformation potential mechanism dominates the generation of the CAP. The results provide insight into the ultrafast optical coherent acoustic phonon and optoelectronic properties of PdSe2, suggesting new possibilities for PdSe2 applications in THz-frequency mechanical resonators.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Materials Science, Ceramics
Tianze Sun, Zongwei Xu, Jintong Wu, Yexin Fan, Fei Ren, Ying Song, Long Yang, Pingheng Tan
Summary: This study investigated the mechanism of defect formation during ion implantation for color center preparation. The samples were characterized by photoluminescence spectrum and electron paramagnetic resonance. It was found that hydrogen ion implantation had an optimal implantation fluence for the formation of VCVSi and VV color centers. Molecular dynamics simulation and experimental results were compared to confirm the existence of the optimal implantation fluence.
CERAMICS INTERNATIONAL
(2023)
Article
Chemistry, Multidisciplinary
Yixuan Huang, Hui Zhao, Zhilin Li, Lili Hu, Yanling Wu, Fei Sun, Sheng Meng, Jimin Zhao
Summary: The observation of the optical Kerr effect in 3D Weyl semimetal TaAs flakes is reported, and the obtained nonlinear susceptibility exhibits a surprisingly high value. These observations extend the understanding of SSPM from 2D to 3D quantum materials and from electron coherence to hole coherence.
ADVANCED MATERIALS
(2023)
Article
Optics
Yang Liu, Jimin Zhao, Zhiyi Wei, Franz X. Kartner, Guoqing Chang
Summary: We present high-power longwave mid-infrared ultrafast sources by utilizing a high-power Er-fiber laser system operating at 1.55 μm with a repetition rate of 32 MHz. Our current configuration enables tighter focusing in the GaSe crystal compared to previous 1.03 μm-driven difference frequency generation (DFG) due to an increased damage threshold at 1.55 μm. As a result, the 1.55 μm-driven DFG operates in the regime of optical parametric amplification (OPA), leading to exponential growth of mid-infrared power with respect to the square root of the pumping power. Experimental demonstration shows broadband mid-infrared pulses tunable in the 7.7-17.3 μm range with a maximum average power of 58.3 mW, which is also verified by numerical simulation.
Article
Chemistry, Multidisciplinary
Tao Sun, Chun Zhou, Hongli Guo, Zhi Meng, Xinyu Liu, Zhou Wang, Han Zhou, Yuming Fei, Kang Qiu, Fapei Zhang, Bolin Li, Xuetao Zhu, Fang Yang, Jimin Zhao, Jiandong Guo, Jin Zhao, Zhigao Sheng
Summary: This article demonstrates a method to generate GHz optical birefringence in SrTiO3 crystals and manipulate it. By using ultrafast laser pumping, low damping coherent acoustic phonons are created in the transducer/STO structures. Through studying a series of transducer layers, a semiconducting LaRhO3 film with relatively high photon-phonon conversion efficiency is obtained. The most interesting finding is that the GHz optical birefringence induced by coherent acoustic phonons in STO exhibits crystal orientation dependence. Optical manipulation of both coherent phonons and its induced GHz birefringence by double pump technique is also achieved.
Article
Chemistry, Multidisciplinary
Xue Chen, Sven Reichardt, Miao-Ling Lin, Yu-Chen Leng, Yan Lu, Heng Wu, Rui Mei, Ludger Wirtz, Xin Zhang, Andrea C. Ferrari, Ping-Heng Tan
Summary: Graphene is used as a platform to study quantum interference pathways by adjusting doping or laser excitation energy. The Raman excitation profile of graphene can provide insights into the lifetimes of intermediate electronic excitations and quantum interference. By tuning the laser excitation energy, the Raman scattering pathways in doped graphene are controlled. Doping-enhanced electron-electron interactions dominate the lifetimes of Raman scattering pathways and weaken Raman interference.
Article
Chemistry, Multidisciplinary
He Hao, Miao-Ling Lin, Bo Xu, Heng Wu, Yuechen Wang, Hailin Peng, Ping-Heng Tan, Lianming Tong, Jin Zhang
Summary: The characterization of interlayer coupling in two-dimensional van der Waals heterostructures (vdWHs) is crucial for understanding their quantum behaviors and structural functionalities. Twisted bilayer graphene (tBLG) provides a universal strategy to enhance layer-breathing (LB) phonons in vdWHs. By resonantly exciting electrons in tBLG, LB phonons extended over the entire layers in vdWHs can be strongly coupled, and this coupling can be tuned by the twist angle of tBLG. This method of enhancing LB phonons by tBLG is promising for investigating electron-phonon coupling and interlayer interaction in related vdWHs.
Article
Physics, Applied
Yan Zhou, Shi Zhou, Shun Wan, Bo Zou, Yuxia Feng, Rui Mei, Heng Wu, Naoteru Shigekawa, Jianbo Liang, Pingheng Tan, Martin Kuball
Summary: A GaN/Si heterointerface without any buffer layer has been successfully fabricated at room temperature through surface activated bonding, solving the problem of lattice and thermal expansion coefficient mismatches between GaN and Si. The residual stress states and interfacial microstructures of the GaN/Si heterostructures were systematically investigated. It was found that the GaN layers bonded to Si by surface activated bonding exhibited significantly relaxed and uniform small tensile stress, mainly attributed to the amorphous layer formed at the bonding interface. Appropriate thermal annealing was found to significantly tune the interfacial microstructure and stress states of bonded GaN/Si heterointerfaces. This work enables the direct integration of GaN with Si CMOS technology with high quality thin interfaces and holds great potential for wafer-scale low-cost fabrication of GaN electronics.
APPLIED PHYSICS LETTERS
(2023)
Article
Physics, Multidisciplinary
Wen-Guang Zhou, Dong-Wei Jiang, Xiang-Jun Shang, Dong-Hai Wu, Fa-Ran Chang, Jun-Kai Jiang, Nong Li, Fang-Qi Lin, Wei-Qiang Chen, Hong-Yue Hao, Xue-Lu Liu, Ping-Heng Tan, Guo-Wei Wang, Ying-Qiang Xu, Zhi-Chuan Niu
Summary: In this study, we compared the photoluminescence (PL) properties of AlInAsSb digital alloy samples with different periods grown on GaSb (001) substrates by molecular beam epitaxy. The temperature-dependent S-shape behavior was observed and explained using a thermally activated redistribution model within a Gaussian distribution of localized states. There are two different mechanisms for the origin of the PL intensity quenching in the AlInAsSb digital alloy. The high-temperature activation energy E (1) is positively correlated with the interface thickness, while the low-temperature activation energy E (2) is negatively correlated with the interface thickness. A quantitative high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) study showed that the interface quality improves as the interface thickness increases. Our results confirmed that E (1) comes from carrier trapping at a state in the InSb interface layer, while E (2) originates from the exciton binding energy due to the roughness of the AlAs interface layer.
Article
Chemistry, Multidisciplinary
Yufei Sun, Shujia Yin, Ruixuan Peng, Jia Liang, Xin Cong, Yi Li, Chenyu Li, Bolun Wang, Miao-Ling Lin, Ping-Heng Tan, Chunlei Wan, Kai Liu
Summary: In this study, an abnormal Raman behavior, the absence of the A1g mode, is observed in cetyltrimethylammonium bromide (CTAB)-intercalated MoS2 superlattice. This abnormal behavior is different from the softening of the A1g mode induced by surface engineering or electric-field gating. Interestingly, the A1g peak gradually appears under strong laser illumination, heating, or mechanical indentation, accompanied by the migration of intercalated CTA+ cations. The abnormal Raman behavior is mainly attributed to the constraint of the out-of-plane vibration due to intercalations and resulting severe electron doping. Our work provides new insights into the Raman spectra of 2D semiconducting materials and offers a new approach for developing next-generation devices with tunable structures.
Article
Chemistry, Multidisciplinary
Qundong Fu, Xin Cong, Xiaodong Xu, Song Zhu, Xiaoxu Zhao, Sheng Liu, Bingqing Yao, Manzhang Xu, Ya Deng, Chao Zhu, Xiaowei Wang, Lixing Kang, Qingsheng Zeng, Miao-Ling Lin, Xingli Wang, Bijun Tang, Jianqun Yang, Zhili Dong, Fucai Liu, Qihua Xiong, Jiadong Zhou, Qijie Wang, Xingji Li, Ping-Heng Tan, Beng Kang Tay, Zheng Liu
Summary: 2D Tellurene (2D Te) exhibits a strong nonlinear optical response in the infrared region due to its unique structure, making it a promising candidate for efficient nonlinear semiconductors. The large second-order nonlinear optical susceptibility (chi(2)) of 2D Te is significantly higher than that of other 2D materials, reaching a peak value at approximately 2300 nm. The exceptional performance is attributed to the presence of large Berry curvature dipole (BCD) located at the Weyl points of 2D Te.
ADVANCED MATERIALS
(2023)
Review
Chemistry, Analytical
Heng Wu, Miao-Ling Lin, Yan Zhou, Xin Zhang, Ping-Heng Tan
ANALYTICAL CHEMISTRY
(2023)
Article
Physics, Applied
Heng Wu, Yan Zhou, Yu-Xin Cai, Miao-Ling Lin, Lijun Zhang, Ping-Heng Tan
Summary: In this study, the interlayer modes in few-layer InSe were systematically investigated using low-frequency Raman spectroscopy. It was found that the commonly used linear chain model is inadequate in accurately describing the frequencies of interlayer shear modes in InSe due to the influence of weak in-plane intralayer In-In bonding. Our study reveals the non-negligible contribution of weak intralayer bonding to the corresponding interlayer vibrations in two-dimensional materials.
APPLIED PHYSICS LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Seda Kutkan, Balaji Dhanabalan, Miao-Ling Lin, Ping-Heng Tan, Alexander Schleusener, Milena P. Arciniegas, Roman Krahne
Summary: Organic-inorganic low-dimensional layered metal-halide perovskites are semiconductors with tunable optoelectronic properties. The interaction between organic cations and the inorganic lattice leads to lattice distortions that affect the band structure and exciton energy levels. The number of peaks in the band-edge emission and their decay dynamics depend on the type of organic cation and the induced lattice distortions. The involvement of phonons and higher order phonon scattering processes in exciton recombination dynamics contribute to thermal broadening of the emission linewidth.
Article
Optics
Xiaodan Xu, Meng Wang, Yaqing Zhang, Qifan Li, Wenshuo Niu, Yifan Yang, Jimin Zhao, Yanling Wu
Summary: Black phosphorus and violet phosphorus exhibit excellent broadband spatial self-phase modulation effects, making them potential candidates for nonlinear optics. By adjusting the intensity of the control beam, the nonlinear optical response of the signal beam can be improved. This study provides an interesting foundation for future applications of phosphorus allotropes in broadband nonlinear photonics.
LASER & PHOTONICS REVIEWS
(2023)
Article
Chemistry, Multidisciplinary
Wenjie Hao, Minghui Gu, Zhenyun Tian, Shaohua Fu, Meng Meng, Hong Zhang, Jiandong Guo, Jimin Zhao
Summary: By employing ultrafast spectroscopy, this study uncovers the spatial separation between electron-phonon coupling (EPC) and phonon-phonon scattering (PPS), providing a vital foundation for designing future quantum nano devices.
