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飞秒激光在6H SiC晶体表面制备纳米微结构 总被引:2,自引:0,他引:2
激光诱导周期性纳米微结构在多种材料包括电介质、半导体、金属和聚合物中观察到。研究了800nm和400nm飞秒激光垂直聚焦于6H SiC晶体表面制备纳米微结构。实验观察到800nm和400nm线偏光照射样品表面分别得到周期为150nm和80nm的干涉条纹,800nm圆偏振激光单独照射样品表面得到粒径约100nm的纳米颗粒。偏振相互垂直的800nm和400nm激光同时照射晶体得到粒径约100nm的纳米颗粒阵列,该纳米阵列的方向随400nm激光强度增加而向400nm偏振方向偏转。利用二次谐波的观点对以上纳米结构的形成给出了解释。 相似文献
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E. V. Barmina A. A. Serkov G. A. Shafeev E. Stratakis C. Fotakis 《Physics of Wave Phenomena》2014,22(1):15-18
The formation of nanostructures on the surface of single-crystal silicon carbide under ablation by femtosecond laser pulses in liquid ethanol has been experimentally investigated. A 800-nm Ti:sapphire laser with a pulse duration of 210 fs was used as a radiation source. Single-scan irradiation of SiC surface leads to the formation of periodic grooves with a period of about 200 nm. Double exposure with a sample rotation by 90° between the scans gives rise to a regular array of nanostructures with average lateral size of 10 to 15 nm. It is determined that the wettability of nanostructured SiC surface is improved in comparison with the initial surface. It is shown that nanostructuring of SiC surface leads to an increase in the red light transmission by a factor of more than 60. 相似文献
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Femtosecond pulse laser-induced self-organized nanostructures on the surface of ZnO crystal
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This paper reports self-organized nanostructures observed on the surface of ZnO crystal after irradiation by a focused beam of a femtosecond Ti:sapphire laser with a repetition rate of 250kHz. For a linearly polarized femtosecond laser, the periodic nanograting structure on the ablation crater surface was promoted. The period of self-organization structures is about 180 nm. The grating orientation is adjusted by the laser polarization direction. A long range Bragglike grating is formed by moving the sample at a speed of 10μm/s. For a circularly polarized laser beam, uniform spherical nanoparticles were formed as a result of Coulomb explosion during the interaction of near-infrared laser with ZnO crystal. 相似文献
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利用波长为800 nm的飞秒激光,在空气和去离子水中诱导钛表面形成不同的周期条纹结构。在空气中,激光能量密度为0.265 J/cm2时,钛表面主要形成周期为500~560 nm低空间频率条纹结构;激光能量密度为0.102 J/cm2时,主要形成的是周期为220~340 nm高空间频率条纹结构。两种条纹均垂直于入射激光偏振方向,且条纹周期随着脉冲重叠数的增大而增大。在水中,除形成垂直激光偏振方向、周期为215~250 nm的高空间频率条纹结构,还形成了平行于激光偏振方向且周期约为入射激光波长八分之一的高空间频率条纹结构。利用表面等离子体理论、二次谐波及Sipe理论对各种周期条纹结构的形成机理进行分析,发现周期条纹结构的形成与钛表面氧化层有密切的关系。 相似文献
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Lingling Ran Zhongyi Guo Shiliang Qu 《Applied Physics A: Materials Science & Processing》2010,100(2):517-521
Self-organized periodic surface structures on ZnO have been observed after multiple linearly polarized femtosecond laser pulse
irradiation. The observed self-organized structures are attributed to the second harmonics in the sample surface excited by
the incident laser. The grating orientation could be adjusted by the laser polarization direction. We also find that fluences
play an important role in the formation of self-organized nanostructures. 相似文献
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Weiwei Liang Feng Chen Hao Bian Qing Yang Xianhua Wang Jinhai Si Xun Hou 《Optics Communications》2010,283(11):2385-2389
Periodic surface nanostructures induced by femtosecond laser pulses on polycrystalline ZnO are presented. By translating the sample line-by-line under appropriate irradiation conditions, grating-like nanostructures with an average period of 160 nm are fabricated. The dependence of surface morphologies on the processing parameters, such as laser fluence, pulse number and laser polarization, are studied by scanning electronic microscope (SEM). In addition, photoluminescence (PL) analysis at room-temperature indicates that the PL intensity of the irradiated area increases significantly compared with the un-irradiated area. Using femtosecond laser pulses irradiation to fabricate periodic surface nanostructures on polycrystalline ZnO is efficient, simple and low cost, which shows great potential applications in ZnO-based optoelectronic devices. 相似文献
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报道了三光束飞秒激光干涉在GaP和ZnSe晶体表面诱导二维复合纳米-微米周期结构.改变三束光的偏振组合方式,可以得到不同的纳米-微米复合结构.理论计算了相应偏振条件下光场强度分布、椭偏度分布和偏振方向分布.实验和理论计算结果表明,烧蚀斑上的微米长周期结构是由三光束干涉的强度花样决定,短周期纳米结构是由光场的偏振干涉花样决定.这些研究在纳米材料制备、超高密度光存储以及材料特性周期性调制等方面有很大的应用前景. 相似文献
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X.J. Wu T.Q. Jia F.L. Zhao M. Huang N.S. Xu H. Kuroda Z.Z. Xu 《Applied Physics A: Materials Science & Processing》2007,86(4):491-495
Uniform arrays of periodic nanoparticles with 80-nm period are formed on 6H-SiC crystal irradiated by circularly polarized
400-nm femtosecond laser pulses. In order to understand the formation mechanism, the morphology evolvement as a function of
laser pulse energy and number is studied. Periodic nanoripples are also formed on the sample surface irradiated by linearly
polarized 400-, 510- and 800-nm femtosecond laser pulses. All these results support well the mechanism that second-harmonic
generation plays an important role in the formation of periodic nanostructures.
PACS 79.20.Ds; 42.62.Cf; 61.80.Ba; 81.05.Cy; 78.30.Am 相似文献
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Periodic nanostructures are observed inside silica glass after irradiation by a focused beam of a femtosecond Ti:sapphire laser. Backscattering electron images of the irradiated spot reveal a periodic structure of stripelike regions of approximately 20 nm width with a low oxygen concentration, which are aligned perpendicular to the laser polarization direction. These are the smallest embedded structures ever created by light. The period of self-organized grating structures can be controlled from approximately 140 to 320 nm by the pulse energy and the number of irradiated pulses. The phenomenon is interpreted in terms of interference between the incident light field and the electric field of the bulk electron plasma wave, resulting in the periodic modulation of electron plasma concentration and the structural changes in glass. 相似文献
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Danilov P. A. Kudryashov S. I. Rupasov A. E. Smirnov N. A. Oleynichuk E. A. Rivnyuk A. S. Zakoldaev R. A. 《JETP Letters》2021,113(10):622-625
JETP Letters - Periodic nanostructures with a period of about 100–150 nm are formed on the surface of nanoporous silicate glass irradiated by sharply-focused laser pulses with a wavelength of... 相似文献
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Through femtosecond (fs) laser pulse irradiation (pulse duration: 65 fs, central wavelength: 800 nm, and repetition rate: 250 Hz), we investigate the morphological evolution of fs laser-induced periodic surface structure on Au and Pt, called a nanostructure-covered large-scale wave (NC-LSW) with a period of tens of microns, densely covered by iterating stripe patterns of nanostructures and microstructures. We show that the surface morphology of NC-LSW crucially depends on the fluence of the laser, the number of irradiating pulses, and the incident beam angle. Our experimental observations allow us to establish a three-step model for the NC-LSW formation: the formation of laser-induced surface unevenness, inhomogeneous energy deposition due to the interference between the incident light and the scattered field, and nonuniform energy deposition due to shielding by the peaks of LSW. 相似文献
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C. W. Cheng W. C. Shen C. Y. Lin Y. J. Lee J. S. Chen 《Applied Physics A: Materials Science & Processing》2010,101(2):243-248
A method is proposed for the fabrication of micro/nano crystalline indium tin oxide (c-ITO) structures using a Ti:Sapphire
laser with a repetition rate of 1 kHz and a wavelength of 800 nm. In the proposed approach, an amorphous ITO (a-ITO) thin
film is transformed into a c-ITO micro/nano structure over a predetermined area via laser beam irradiation, and the residual
a-ITO thin film is then removed using an etchant solution. The fabricated c-ITO structures are observed using scanning electron
microscopy (SEM) and cross-sectional transmission electron microscopy (TEM). The observation results show that the use of
a low repetition rate laser induces a high thermal cycling effect within the ITO film and therefore prompts the formation
of micro-cracks in the c-ITO structure. In addition, it is shown that as the laser power approaches the ablation threshold
of the a-ITO thin film, nanogratings and disordered nanostructures are formed along the center lines of the c-ITO patterns
formed using linearly polarized and circularly polarized laser beam irradiation, respectively. The nanogratings are found
to have a period of approximately 200 nm (i.e. one-quarter of the irradiation wavelength), while the nanostructures have an
average diameter of approximately 100–160 nm. 相似文献
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E. V. Golosov V. I. Emel’yanov A. A. Ionin Yu. R. Kolobov S. I. Kudryashov A. E. Ligachev Yu. N. Novoselov L. V. Seleznev D. V. Sinitsyn 《JETP Letters》2009,90(2):107-110
One-dimensional quasiperiodic structures whose period is much smaller than the wavelength of exciting radiation have been obtained on a titanium surface under the multipulse action of linearly polarized femtosecond laser radiation with various surface energy densities. As the radiation energy density increases, the one-dimensional surface nanorelief oriented perpendicularly to the radiation polarization evolves from quasiperiodic ablation nanogrooves to regular lattices with subwave periods (100–400 nm). In contrast to the preceding works for various metals, the period of lattices for titanium decreases with increasing energy density. The formation of the indicated surface nanostructures is explained by the interference of the electric fields of incident laser radiation and a surface electromagnetic wave excited by this radiation, because the length of the surface electromagnetic wave for titanium with significant interband absorption decreases with an increase in the electron excitation of the material. 相似文献
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H.L. Ma Y. Guo M.J. Zhong R.X. Li 《Applied Physics A: Materials Science & Processing》2007,89(3):707-709
Periodic nanostructures are observed on the surface of ZnSe after irradiation by a focused beam of a femtosecond Ti:sapphire
laser, which are aligned perpendicular to the laser polarization direction. The period of self-organized grating structures
is about 160 nm. The phenomenon is interpreted in terms of interference between the incident light field and the surface scattered
wave of 800-nm laser pulses. With the laser polarization parallel to the moving direction we produce long-range Bragg-like
gratings by slowly moving the crystal under a fixed laser focus. The nanograting orientation is adjusted by laser polarization
and the accumulation effect.
PACS 81.16.Rf; 78.67.-n; 33.80.Rv; 82.53.Mj; 81.16.-c 相似文献