Article
Physics, Applied
Hang Liu, Yuning Wang, John McCain, Liqiang Feng
Summary: The spatial inhomogeneous effect of laser pulses on the enhancement of single-order harmonic has been theoretically investigated. The results show that symmetric and negative inhomogeneous laser pulses exhibit similar phenomena in enhancing single-order harmonic. The blue-shift of the single-order harmonic enhancement is observed with an increase in the inhomogeneous parameter. In the case of positive inhomogeneous effect, multiple harmonic enhancements are observed instead of single-order harmonic enhancement. The change of single-order harmonic enhancement with inhomogeneous effect is attributed to the time-frequency analyses of the harmonic emission process.
MODERN PHYSICS LETTERS B
(2022)
Article
Optics
Feng Wang, Zhangtao Xiong, Xiaofan Zhang, Qing Liao, Peixiang Lu
Summary: The study investigates the photoemission process of the hydrogen atom in a spatial-dependent infrared field, revealing that the inhomogeneous field induces an additional influence on the photoemission time delay. A method is demonstrated to extract the crucial parameter characterizing the spatial distribution of the IR field based on the photoemission time delay in the inhomogeneous field, potentially providing a pathway towards describing plasmon-enhanced fields near a nanostructure.
Article
Optics
V. A. Birulia, M. A. Khokhlova, V. V. Strelkov
Summary: This study investigates the attosecond properties of coherent extreme ultraviolet (XUV) generated via high-order frequency mixing (HFM) through theoretical and numerical analysis. The research finds that the duration and carrier-envelope phase of the attosecond pulses generated by HFM can be effectively controlled, especially when one of the generating fields has much lower frequency and intensity compared to the other.
Article
Physics, Multidisciplinary
J. P. Kennedy, B. Dromey, M. Yeung
Summary: Bright attosecond pulses of extreme ultraviolet and x-ray radiation can be generated when intense light is incident on a solid target. A non-collinear gating scheme allows for the extraction of a single intense attosecond pulse from the train of pulses.
NEW JOURNAL OF PHYSICS
(2022)
Article
Chemistry, Physical
Hang Liu, Xiaodan Jing, Liqiang Feng
Summary: By combining the time and space waveform optimization method, optimal waveforms for producing high order harmonic spectra with positive and negative inhomogeneous 3-color laser pulses have been identified. The results are explained through the time-space profiles of the laser pulse and time-profile of the harmonic emission process, ultimately leading to the generation of ultra-short isolated 40 as pulses when harmonics are properly superposed.
CHEMICAL PHYSICS LETTERS
(2021)
Article
Optics
Vasily V. Strelkov, Margarita A. Khokhlova
Summary: In this study, we investigate the production of an isolated attosecond pulse through phase-matching gating technique and intense laser pulses. We study the XUV energy as a function of propagation distance and find the upper limit of the fundamental pulse duration for attosecond pulse generation.
Article
Physics, Multidisciplinary
Yi Zhang, Conglin Zhong, Shaoping Zhu, Xiantu He, Bin Qiao
Summary: This article proposes a novel method to generate far-field isolated attosecond pulses (IAPs) by controlling divergences of different pulses, and it is realized through relativistic chirped laser-plasma interactions. By adjusting the distance between plasma targets and laser foci, and utilizing various wavefronts for different cycles of incident chirped lasers, the reflected harmonics with the minimum divergences can be obtained, resulting in the isolation of the corresponding attosecond pulse in the far field.
NEW JOURNAL OF PHYSICS
(2022)
Article
Optics
Rambabu Rajpoot, Amol R. Holkundkar, Jayendra N. Bandyopadhyay
Summary: In this study, high harmonic generation (HHG) using elliptically polarized two-color driving fields was explored as a promising source of circularly polarized ultrashort XUV radiation at the attosecond time scale. The polarization of the attosecond pulses (APs) can be controlled by adjusting the emitted harmonics' ellipticity through modifying the driver fields. A clear scaling for the ellipticity of the APs was deduced by solving the time-dependent Schrodinger equation in two dimensions, allowing for the generation of APs with desired degrees of polarization ranging from linear to elliptical to circular.
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
(2021)
Article
Physics, Applied
Hang Liu, Xiaodan Jing, Yan Qiao, John McCain, Liqiang Feng
Summary: This paper investigates the waveform control of high-order harmonic generation and attosecond pulse generation from different initial states of He atom. It shows that controlling the carrier-envelope phases, time delays, and laser intensities of a 3-color laser pulse can lead to optimal waveforms for harmonic cut-off extension. Additionally, the introduction of inhomogeneous effects can further extend harmonic cut-offs, despite decreasing harmonic intensities from superposition initial states compared to homogeneous pulses. Furthermore, choosing the ground state as the initial state and using a 4th UV pulse can result in larger harmonic cut-offs and stronger harmonic plateaus for producing intense attosecond pulses.
MODERN PHYSICS LETTERS B
(2021)
Article
Optics
Ahmad Reza Madhani, Elnaz Irani, Mohammad Monfared
Summary: This paper theoretically investigates the generation of isolated elliptically polarized attosecond pulses from the interaction of Cl2 molecule and a polarization-gating laser pulse. Two methods are proposed, one using a single-color laser and controlling the molecule orientation angle, and the other using a two-color laser and adjusting the intensity ratio. The achieved attosecond pulses have different ellipticities and pulse durations.
Article
Optics
Yongkun Chen, Yueming Zhou, Jia Tan, Min Li, Wei Cao, Peixiang Lu
Summary: Photoelectron holography in strong-field tunneling ionization is an efficient way to probe the structures and ultrafast dynamics of atoms and molecules. Manipulating the holography process is important for its application. The study shows that in a spatially inhomogeneous field, the returning energy of rescattering electrons is enhanced and the holographic interference pattern can be separated from other types of interference in the photoelectron momentum distribution. Additionally, the time window for tunneling ionization in which the electron can induce holography is broadened in the inhomogeneous field.
Article
Physics, Multidisciplinary
Rishat Zagidullin, Stefan Tietze, Matt Zepf, Jingwei Wang, Sergey Rykovanov
Summary: This paper investigates the dynamics of single attosecond pulse generation from a relativistically oscillating plasma mirror. It finds that the required carrier-envelope phase for generating a single attosecond pulse is different from previous expectations due to the relative plasma density and preplasma scale length.
MATTER AND RADIATION AT EXTREMES
(2023)
Article
Optics
Shilin Hu, Xiaopeng Yi, Li Guo, Chengrui Bi, Jing Chen
Summary: This study investigates the excitation process of a hydrogen atom in Rydberg states under spatially homogeneous and inhomogeneous laser fields using ab initio calculations. The results show that, compared with atoms exposed to homogeneous fields, the excitation probability decreases in spatially inhomogeneous laser pulses, and the electron tends to occupy states with lower quantum numbers. Additionally, calculations based on a quantum model that neglects ionization after coherent capture by the Rydberg state are inconsistent with the findings from the ab initio calculations. Analysis suggests that the enhanced ionization of Rydberg states by inhomogeneous laser fields is responsible for these intriguing features, as the distributions of high quantum number Rydberg states are located far from the core where the inhomogeneous electric fields are significant.
Article
Physics, Multidisciplinary
Yueying Liang, Xinkui He, Kun Zhao, Hao Teng, Zhiyi Wei
Summary: This article theoretically investigates the generation of isolated attosecond pulses in argon at different gas pressures and medium lengths. It is found that the output of attosecond pulses can be effectively enhanced by using a longer gas medium with optimized pressure.
Article
Physics, Multidisciplinary
R. E. Smith, E. White, P. M. Gilmore, B. Dromey, M. Yeung
Summary: The research found that a double optical gating scheme using a second harmonic field and counter-rotating circularly polarized laser pulses can generate attosecond pulses more efficiently and improve temporal isolation compared to a single color polarization gating scheme.
NEW JOURNAL OF PHYSICS
(2021)
Article
Optics
Hang Dong, Zhixin Sun, Jingyi Li, Yahui Li, Wei Zhang, Guangyong Jin
Summary: This paper calculates thermal stresses and adsorption forces to determine laser cleaning conditions and establishes relevant models. Experimental results show that the removal effect is better with increasing nanosecond pulse delay, with the best effect achieved at 600 milliseconds pulse delay. Based on the findings, the mechanisms of oxide film removal involve thermal stress against adsorption and plasma shock wave breaking the oxide layer.
OPTICS COMMUNICATIONS
(2024)
Article
Optics
Junjie Zhang, Wenjun Li, Bingtao Li, Zheng-Da Hu, Jicheng Wang, Feng Zhang, Lei Wang
Summary: A multilayer thin film device structure based on Tamm plasmons is proposed for high-performance near-infrared hot electron photodetectors. By optimizing the device structure parameters, high responsivity detection can be achieved.
OPTICS COMMUNICATIONS
(2024)
Article
Optics
Hong Huang, Zhiguang Han
Summary: This paper proposes a new ghost imaging reconstruction method using ordered orthogonal Hadamard derived speckle as the illumination speckle series, and introduces the alternating direction multiplier method to improve the imaging performance. The evaluation results show that the method can achieve high-quality reconstructed images under low sampling conditions.
OPTICS COMMUNICATIONS
(2024)
Article
Optics
Moritsugu Sakamoto, Yuki Ono, Kohei Noda, Tomoyuki Sasaki, Nobuhiro Kawatsuki, Masayuki Tanaka, Hiroshi Ono
Summary: The effect of wavelength and polarization of illuminating light in polarization imaging for birefringent objects placed behind a scattering structure was experimentally investigated. The result shows that the spatial distribution of the birefringent object was more clearly visualized in the longer wavelength combined with circularly polarized light illumination. This finding indicates the potential of using polarization imaging with circularly polarized light illumination in the near-infrared range for visualizing birefringent objects with scattering.
OPTICS COMMUNICATIONS
(2024)
Article
Optics
Peihui Du, Hongfang Wang, Pengwei Li, Rukeyemuhan Abadula, Hmbat Batelbek, Min Gao
Summary: In this study, we theoretically demonstrate the strong coupling between Tamm plasmons and exciton polaritons in metal Al/DBR-molecular structures, extending the operating wavelength to the deep ultraviolet region. The coupling strength can be effectively manipulated by adjusting the structure parameters, offering potential benefits for the development of new-style optical filters.
OPTICS COMMUNICATIONS
(2024)
Article
Optics
Priyanka Chaudhary, Akhilesh Kumar Mishra
Summary: We design and numerically investigate the switching dynamics between two outer waveguides in a parity-time (PT)-symmetric adiabatically coupled three waveguides nonlinear directional coupler (NLDC) system. The study shows that the device can provide switching even when the middle waveguide is nonlinear and the outer waveguides are linear. Furthermore, the effect of loss to gain ratio on critical switching power and the impact of launched light power and gain (loss) value on transmitted power are also studied.
OPTICS COMMUNICATIONS
(2024)
Article
Optics
Wei Feng, Yongcong Yi, Shuyang Li, Zhi Xiong, Boya Xie, Zhen Zeng
Summary: Traditional imaging techniques are ineffective in achieving clear underwater imaging due to the presence of scattering media. Single-pixel imaging (SPI) system based on Unet++ offers a solution for reconstructing high-quality images in highly turbid water environments.
OPTICS COMMUNICATIONS
(2024)
Article
Optics
Xiaorui Qu, Jufeng Zhao, Haijun Tian, Junjie Zhu, Guangmang Cui
Summary: This paper studies the structural similarity between RGB and spectral images and proposes a non-iterative Images Structure Similarity (ISS) method for fast reconstruction of spectral images. Additionally, the input of the Deep Image Prior (DIP) method is optimized for the first time by using the initial spectral data reconstructed by ISS, leading to an improved starting value for the iteration. The experimental results show that the proposed method can enhance the reconstruction quality in both spectral and spatial resolutions, while significantly reducing the reconstruction time compared to other DIP-based methods.
OPTICS COMMUNICATIONS
(2024)
Article
Optics
Donghe Sheng, Zhe Han, Zanyang Qiao, Tianpei Dong, Chenxi Wang, Huiping Tian
Summary: In this study, a distributed multi-parameter sensor based on an etched few-mode multi-core fiber is proposed, allowing simultaneous sensing of temperature, strain, and sample refractive index. By combining space division multiplexing and stimulated Brillouin scattering, the sensor achieves high sensitivity in detecting these parameters.
OPTICS COMMUNICATIONS
(2024)
Article
Optics
Dehao Chen, Zhenwu Mo, Zehong Liang, Junjie Jiang, Huilin Tang, Yidan Sun, Ziyu Wang, Quanfeng Wei, Yanru Chen, Dongmei Deng
Summary: In this study, a novel family of elliptical Airyprime vortex beams (EAPVBs) is introduced, which inherits the excellent self-focusing properties of the circular Airyprime vortex beam (CAPVB). The asymmetric focusing of EAPVB leads to some novel properties, such as the splitting of high-order optical vortex and the formation of two foci. By taking advantage of these properties, EAPVB is constructed as a tunable optical bottle for particle capture.
OPTICS COMMUNICATIONS
(2024)
Article
Optics
Xiao Ma, Qiongchan Shao, Jian-Jun He
Summary: In this study, an SHS chip based on Su8 waveguide was designed and fabricated. By physically adjusting the metal electrodes and compensating for transmissivity fluctuations, the generation of side ripples was successfully suppressed.
OPTICS COMMUNICATIONS
(2024)
Article
Optics
Hongbin Zhang, Jiansen Du, Zongtao Chi, Hailin Cong, Bin Wang
Summary: In this paper, a novel type of dual-wavelength confocal metalens is proposed to solve the spatial crosstalk between two wavelengths. The metalens can greatly reduce the spatial crosstalk and achieve high precision and efficiency in confocal imaging. It can also focus light in specific wavelength ranges, making it suitable for imaging, microscopy, and optical fiber communication.
OPTICS COMMUNICATIONS
(2024)
Article
Optics
Rui Qiu, Guanmao Zhang, Shaokai Du, Jie Liu, Hongyu Jib, Kaiyun Bi, Bochuan Xing, Guangchao Diao
Summary: Recent research has developed an achromatic metalens that shows potential for replacing traditional lenses. This study focuses on a continuously variable focus height broadband achromatic metalens for long-wavelength infrared applications. By optimizing materials and parameters, chromatic aberration is effectively corrected, making it suitable for high-resolution LWIR imaging and spectroscopy systems.
OPTICS COMMUNICATIONS
(2024)
Article
Optics
Marcos Troncoso-Costas, Gaurav Jain, Yiming Li, Mohammed Patel, Lakshmi Narayanan Venkatasubramani, Sean O'Duill, Frank Smyth, Andrew Ellis, Francisco Diaz-Otero, Colm Browning, Liam Barry
Summary: In this work, a fast-switching tuneable laser capable of wide wavelength coverage, low noise and linewidth levels suitable for high-order modulation formats is demonstrated. The laser is characterized to cover a wavelength range of 35 nm in the C-band with nanosecond switching time. It is used to successfully demonstrate 480 Gbit/s 16QAM transmission over 25 km of single-mode fiber for a wavelength range of 19 nm.
OPTICS COMMUNICATIONS
(2024)
Article
Optics
Takeshi Moriyasu, Masahiko Tani, Hideaki Kitahara, Takashi Furuya, Jessica Afalla, Toshiro Kohmoto, Daishiro Koide, Hiroki Sato, Mitsutaka Kumakura
Summary: Optical pump-terahertz probe spectroscopy was used to study the photocarrier dynamics and optical characteristics of semiconductor Si. The results showed that the thickness of Si influenced the transmitted terahertz field amplitude and peak delay time, indicating differences in photocarrier dynamics between different Si materials.
OPTICS COMMUNICATIONS
(2024)