Article
Chemistry, Physical
Beatriz Martin-Garcia, Davide Spirito, Giulia Biffi, Sergey Artyukhin, Francesco Bonaccorso, Roman Krahne
Summary: Halide double perovskites are a promising alternative to Pb-containing materials in optoelectronic devices. By introducing large organic cations, researchers successfully synthesized layered double perovskites, and observed changes in the conformational arrangement of organic cations during phase transitions. Raman spectroscopy and photoluminescence intensity changes provide important insights into the structural variations.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Engineering, Electrical & Electronic
J. Abhishek, Prabu Krishnan, S. Robinson
Summary: A novel passive all-optical full subtractor device is proposed in this study, utilizing a two-dimensional photonic crystal and the concept of beam interference. By avoiding the use of nonlinear materials and semiconductor optical amplifiers, the device achieves a fast response time, high bit rate, and good contrast ratio through simulations and optimizations.
JOURNAL OF COMPUTATIONAL ELECTRONICS
(2021)
Article
Chemistry, Multidisciplinary
Eva Arianna Aurelia Pogna, Michele Celebrano, Andrea Mazzanti, Lavinia Ghirardini, Luca Carletti, Giuseppe Marino, Andrea Schirato, Daniele Viola, Paolo Laporta, Costantino De Angelis, Giuseppe Leo, Giulio Cerullo, Marco Finazzi, Giuseppe Della Valle
Summary: Enhancing nonlinear optical effects through nanoscale engineering is a hot research topic. Experimental demonstration of ultrafast all-optical modulation of the second harmonic from a single nanoantenna has the potential to lead to the development of nonlinear nanophotonic devices for a wide range of communication and sensing applications.
Article
Chemistry, Physical
Wei-Long Xu, Jiaheng Huang, Yuebin Lian, Xiaoyu Yang, Yannan Zhang
Summary: Lead-free perovskite Cs3Bi2I9 single crystal hexagonal sheets were prepared by solution method with preferred orientation along (002). The growth processes of Cs3Bi2I9 crystal were revealed by in-situ optical and structural observation. Cs3Bi2I9 single crystal hexagonal sheets exhibited excellent stability and charge transfer, and planar photodetectors based on them showed good photosensitive property and stability.
APPLIED SURFACE SCIENCE
(2023)
Article
Nanoscience & Nanotechnology
Gordon H. Y. Li, Ryoto Sekine, Rajveer Nehra, Robert M. Gray, Luis Ledezma, Qiushi Guo, Alireza Marandi
Summary: The introduction of energy-efficient hardware accelerators has become necessary in recent years due to the computational demands of deep learning applications. Optical neural networks have shown promise as a potential solution, but their progress has been limited by a lack of energy-efficient nonlinear optical functions. This study demonstrates an all-optical Rectified Linear Unit (ReLU) using a periodically-poled thin-film lithium niobate nanophotonic waveguide, achieving ultra-low energies and near-instantaneous operation. This provides a practical path towards all-optical and energy-efficient nanophotonic deep learning.
Article
Chemistry, Multidisciplinary
Andrea Schirato, Andrea Mazzanti, Remo Proietti Zaccaria, Peter Nordlander, Alessandro Alabastri, Giuseppe Della Valle
Summary: This paper investigates the hot-electron dynamics in nanostructured materials upon irradiation with Is-laser pulses and explores the opportunities for ultrafast diffraction management through the inhomogeneous evolution of hot carriers. The design of a highly symmetric plasmonic metagrating capable of transient symmetry breaking and the control of recovery time for symmetric configurations are discussed in detail.
Article
Physics, Multidisciplinary
Yule Zhang, Feng Zhang, Bowen Du, Hualong Chen, S. Wageh, Omar A. Al-Hartomy, Abdullah G. Al-Sehemi, Bin Zhang, Han Zhang
Summary: All-optical switches have attracted significant attention due to their ultrafast speed compared to electric switches. The exceptional optical properties and strong interaction of two-dimensional (2D) material MXene indicate its great potential in next-generation all-optical switching. In this study, we propose using Au/MXene for all-optical switching with a switching full width at half maximum (FWHM) operating at 290 fs. Compared to pure MXene, the Au/MXene exhibits outstanding performances, such as broadband differential transmission and strong enhancement in near-infrared on/off ratio, due to local surface plasmon resonance (LSPR). Importantly, this research demonstrates a red shift of approximately 34 nm in the ultrafast all-optical switching of Au/MXene compared to MXene, validating its all-optical properties and paving the way for optical interconnection and optical switching.
FRONTIERS OF PHYSICS
(2023)
Article
Optics
Weibao He, Mingyu Tong, Zhongjie Xu, Yuze Hu, Xiang'ai Cheng, Tian Jiang
Summary: This study demonstrates the construction of a terahertz metasurface supported by the EIT effect through inverse design for the first time, showing the potential applications of inverse design in terahertz device design.
PHOTONICS RESEARCH
(2021)
Article
Chemistry, Multidisciplinary
Benjamin Bauer, Rahul Sharma, Majed Chergui, Malte Oppermann
Summary: This study resolves the exciton dynamics of UV-excited adenosine single strands and offers a direct view into the coupling of electronic and structural dynamics in aggregated photochemical systems.
Article
Chemistry, Multidisciplinary
Wenjie Wang, Yao Wang, Runze He, Xiaozheng Wang, Zheng Shen, Xiaocang Han, Alicja Bachmatiuk, Wen Wen, Mark H. Rummeli, Pan Liu, Mengqi Zeng, Lei Fu
Summary: This article reports a peculiar single-crystal-to-single-crystal transformation from organic crystals to inorganic crystals, achieving a drastic change in structure, connectivity, and dimension. This transformation expands the research scope of single-crystal transformations and provides a novel pathway for the synthesis of crystalline materials.
ADVANCED MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Xiaolong Cheng, Ruiwen Shao, Dongjun Li, Hai Yang, Ying Wu, Bin Wang, Chunhao Sun, Yu Jiang, Qiaobao Zhang, Yan Yu
Summary: By rationally designing a self-healing nanostructure 3D continuous bulk porous bismuth (3DPBi), the anode material for sodium-ion batteries demonstrated unprecedented rate capability and long-cycle life. Furthermore, the full cell performance showed stable cycling and high gravimetric energy density, indicating its practical application potential.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Guanyu Liu, Xiaozhi Bao, Weikang Dong, Qi Wei, Haoran Mu, Wenguo Zhu, Bingzhe Wang, Jianding Li, Babar Shabbir, Yuan Huang, Guichuan Xing, Jianhui Yu, Peng Gao, Huaiyu Shao, Xiangping Li, Qiaoliang Bao
Summary: The study reveals that 2D Bi-2212 exhibits profound plasmon absorption and ultrafast carrier dynamics, with tunable nonlinear absorption depending on thickness.
Article
Chemistry, Multidisciplinary
Manish Garg, Alberto Martin-Jimenez, Yang Luo, Klaus Kern
Summary: The unification of ultrafast science techniques and scanning tunneling microscopy has the potential to track electronic motion in molecules in real space and time. By adjusting the DC bias at the STM junction, selective dipole coupling of electronic states by photons can be controlled, allowing for high spatial and temporal resolution.
Article
Engineering, Electrical & Electronic
Yingkui Li, Lei Du, Xin Li, Zonghui Tao, Wanzhuo Ma, Tianshu Wang, Yan Lou, Huilin Jiang
Summary: A noise-like pulse (NLP) thulium-doped fiber laser based on single-wall carbon nanotubes (SWCNTs) is proposed and demonstrated. SWCNTs-decorated microfiber acts as a saturable absorber to generate ultrafast pulses. Experimental results show the generation of NLP with specific parameters under appropriate conditions.
IEEE PHOTONICS JOURNAL
(2022)
Article
Nanoscience & Nanotechnology
Cong Wang, Lingfeng Gao, Hualong Chen, Yiquan Xu, Chunyang Ma, Haizi Yao, Yufeng Song, Han Zhang
Summary: By utilizing transition metal carbide (Nb2C), a method for ultrafast all-optical switching with very small response time and switching energy is proposed using the pump-probe approach. This all-optical switching approach based on 2D materials has the potential to achieve high-performance all-optical devices and play a role in high-speed photonics processing.
Article
Optics
Philipp Schmidt, Andre Knie, Andreas Hans, Kouichi Hosaka, Masatoshi Ukai, Michele Glass-Maujean, Arno Ehresmann
Summary: Fluorescence spectra of H2 molecules excitation by synchrotron radiation have been recorded in a specific energy range, with sufficient resolution to distinguish fluorescent transitions between different rovibronic states. These experiments provide spectroscopic reference data for theory benchmarking and interpreting astrophysical observations.
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
Kunie Ishioka, Terumasa Tadano, Masatoshi Yanagida, Yasuhiro Shirai, Kenjiro Miyano
Summary: Investigation of ultrafast vibrational dynamics of inorganic-organic hybrid lead halide perovskite CH3NH3PbI3 in the room-temperature tetragonal phase under weak photoexcitation reveals frequency blueshifts with increasing pump fluence and heavily damped oscillations. Ab initio lattice dynamics simulations confirm the strong anharmonicity of vibrational potentials for zone-center optical phonon modes as the origin of the experimentally observed frequency blueshifts.
PHYSICAL REVIEW MATERIALS
(2021)
Article
Nanoscience & Nanotechnology
Shunsuke Tanaka, Tatsuya Yoshida, Kazuya Watanabe, Yoshiyasu Matsumoto, Tomokazu Yasuike, Dino Novko, Marin Petrovic, Marko Kralj
Summary: Exploring quantum effects in plasmonic responses has become increasingly popular in recent years. This study demonstrates that quantum effects significantly alter the ultrafast plasmonic response by studying a novel atomically thin multilayer structure. Additionally, localized excitation nonthermally launches surface phonons, exhibiting plasmon band modulation.
Article
Chemistry, Physical
Hayata Yamada, Garrek Stemo, Hiroyuki Katsuki, Hisao Yanagi
Summary: We developed a spacerless flow-cell cavity for the observation of vibrational strong coupling and demonstrated its availability in two samples with a C???N bond: a metal complex (aq) and an ionic liquid. The cavity length can be tuned to investigate coupling with different order Fabry-Pe??rot cavity modes without reassembling the cavity. In the ionic liquid, analysis showed that the Rabi splitting parameters and the square root of the integrated absorption intensity are proportional among the three neighboring vibrational modes. The spacerless cell structure simplifies the comparison of different vibrational strong coupling measurements.
JOURNAL OF PHYSICAL CHEMISTRY B
(2022)
Article
Chemistry, Physical
Naoki Nagatsuka, Noboru Shibata, Toya Muratani, Kazuya Watanabe
Summary: In this paper, the wetting behavior of Pt(533) is studied using vibrational sum-frequency generation spectroscopy. The results show that water molecules on both the step and the terrace have a proton pointing down configuration. The growth manner of the signal and isotopic dilution experiments support a one-dimensional chain with a zigzag structure.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Optics
Sang-Hyuk Park, Sehyuk Lee, Kunie Ishioka, Christopher J. Stanton, Chul-Sik Kee, Andreas Beyer, Ulrich Hoefer, Wolfgang Stolz, Kerstin Volz, Young-Dahl Jho
Summary: We report on a new mechanism of THz electromagnetic emission, which involves the deformational coupling of acoustic phonons and electrons in non-polar Si propagation medium. Local modulation of the bandgap by propagating acoustic phonon pulses induces abrupt drift motion at the depletion edge of Si, resulting in the simultaneous emission of delayed THz bursts.
Article
Chemistry, Physical
Garrek Stemo, Hayata Yamada, Hiroyuki Katsuki, Hisao Yanagi
Summary: Vibrational strong coupling and the formation of vibrational polaritons are the result of strong light-matter interaction. The Rabi splitting parameter reflects the strength of the interaction and provides information about molecular alignment and vibrational motion. In this study, we investigated the vibrational strong coupling in liquid crystal molecules and observed changes in the Rabi splitting with the phase transition, as well as polarization-dependent anisotropy in a specific phase. Our results suggest that the collective vibrational motion inside the cavity affects the molecular properties under the vibrational strong coupling regime.
JOURNAL OF PHYSICAL CHEMISTRY B
(2022)
Article
Physics, Condensed Matter
Yuya Furusho, Ryoko Yagi, Masaki Suda, Tsukasa Maruhashi, Itsuki Takagi, Yosuke Kayanuma, Fujio Minami, Kazutaka G. Nakamura
Summary: Using a pump-probe protocol, we measured the transient reflectivity of a GaAs/Al0.3Ga0.7As multiple quantum well structure at 10 K. Quantum beating between heavy-hole and light-hole excitons was observed, causing oscillations in the reflectivity. The intensity of these oscillations could be controlled by adjusting the delay between the pump pulses. Additionally, interference fringes were observed, indicating the presence of entangled quantum paths for the photo-induced excitons.
SOLID STATE COMMUNICATIONS
(2023)
Article
Physics, Condensed Matter
Itsuki Takagi, Kazutaka G. Nakamura
Summary: The generation of coherent phonons is investigated using a thermal equilibrium phonon distribution as the initial condition. The study calculates the time evolution of the coherent phonon amplitude and phonon population for 4.5-THz phonons with initial distributions at 10 and 300 K. Results show that the coherent-phonon amplitudes of state-selected phonons depend on the initial phonon distribution, while considering all phonon states leads to nearly identical coherent-phonon amplitudes for both initial distributions. The variance of the coherent-phonon amplitudes oscillates with twice the phonon frequency and its oscillation amplitude depends on the initial phonon distribution.
SOLID STATE COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Naoki Nagatsuka, Shota Kamibashira, Noboru Shibata, Takanori Koitaya, Kazuya Watanabe
Summary: In this study, the coadsorption of oxygen atoms and water molecules on Pt(553) was investigated using vibrational sum-frequency generation spectroscopy. The results revealed the formation of hydroxyl species at the steps due to the dissociation of water molecules. The hydrogen bond network of the water and hydroxyl complex was proposed, and the proton configuration of the water network at the terrace was shown to be strongly influenced by oxygen decoration at the step.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Materials Science, Multidisciplinary
Itsuki Takagi, Yosuke Kayanuma, Kazutaka G. Nakamura
Summary: We measured the decoherence time of electronic excited states in n-GaAs crystals using a double pulse excitation method and evaluated it quantitatively with a simple model incorporating temperature dependence. Utilizing ultrafast quantum path interferometry, we observed interference patterns of electronic and phonon coherence in n-GaAs and determined the decoherence time through quantum calculations. The temperature dependence of the decoherence time could be well reproduced by the density of electrons in the conduction band and the group velocity of the photoinduced electrons.
Article
Optics
Tomoya Ikuta, Kouichi Hosaka, Hiroshi Akagi, Fumihiko Kannari, Ryuji Itakura
Summary: In this study, multichannel dissociative ionization of ethanol in intense ultraviolet laser fields was investigated using a photoelectron-photoion coincidence momentum imaging technique. It was found that subsequent electronic excitation rather than photoelectron emission determines the internal energy of ethanol cations.
Article
Materials Science, Multidisciplinary
Kunie Ishioka, Ethan Angerhofer, Christopher J. Stanton, Gerson Mette, Kerstin Volz, Wolfgang Stolz, Ulrich Hoefer
Summary: Transient reflectivity spectroscopy is used to study ultrafast carrier and phonon dynamics in GaP/Si heterostructures. By analyzing the change of Si phonon signal, the interface contribution and the substrate contribution can be separated.
Article
Optics
D. Marion, G. Duchateau, J-C Delagnes
Summary: This paper reports on the properties of a nonconventional stochastic photonic source. By using a modified Mach-Zehnder interferometer, the principle of nonlinear intensity filtering is described, and the statistical properties of light can be tailored. The modified statistics greatly impact simple nonlinear processes.
Article
Optics
Kouichi Hosaka, Yutaro Torizuka, Philipp Schmidt, Arno Ehresmann, Takeshi Odagiri, Masashi Kitajima, Noriyuki Kouchi
Summary: The analytical expression of the angular correlation function of a pair of Lyman-alpha photons in the photo-dissociation of a hydrogen molecule is derived theoretically based on atomic physics, molecular physics, and quantum optics. The function is expressed in terms of cosine and sine functions of four angular variables of detectors with five coefficients. Although a special detector arrangement where the angular-dependent terms vanish does not exist, a special pair of detector arrangements known as a magic pair is found where the angular-dependent terms vanish in the summation of two values of the function.