简介：Highspatialfrequencylaserinducedperiodicsurfacestructures(HSFLs)onsiliconsubstratesareoftendevelopedonflatsurfacesatlowfluencesnearablationthresholdof0.1J/cm2,seldomonmicrostructuresormicrogroovesatrelativelyhigherfluencesabove1J/cm^2.ThisworkaimstoenrichthevarietyofHSFLs-containinghierarchicalmicrostructures,byfemtosecondlaser(pulseduration:457fs,wavelength:1045nm,andrepetitionrate:100kHz)inliquids(waterandacetone)atlaserfluenceof1.7J/cm^2.TheperiodofSi-HSFLsintherangeof110–200nmisindependentofthescanningspeeds(0.1,0.5,1and2mm/s),lineintervals(5,15and20μm)ofscanninglinesandscanningdirections(perpendicularorparalleltolightpolarizationdirection).ItisinterestinglyfoundthatbesidesnormalHSFLswhoseorientationsareperpendiculartothedirectionoflightpolarization,bothclockwiseoranticlockwiserandomlytiltedHSFLswithamaximaldeviationangleof50°ascomparedtothoseofnormalHSFLSsarefoundonthemicrostructureswithheightgradients.RamanspectraandSEMcharacterizationjointlyclarifythatsurfacemeltingandnanocapillarywavesplayimportantrolesintheformationofSi-HSFLs.ThefactthatnoHSFLsareproducedbylaserablationinairindicatesthatmoderatemeltingfacilitatedwithultrafastliquidcoolingisbeneficialfortheformationofHSFLsbyLALs.Onthebasisofourfindingsandpreviousreports,asynergisticformationmechanismforHSFLsathighfluencewasproposedanddiscussed,includingthermalmeltingwiththeconcomitanceofultrafastcoolinginliquids,transformationofthemoltenlayersintoripplesandnanotipsbysurfaceplasmonpolaritons(SPP)andsecond-harmonicgeneration(SHG),andmodulationofSi-HSFLsdirectionbybothnanocapillarywavesandthelocalizedelectricfieldcomingfromtheexcitedlargeSiparticles.

简介：在这份报纸，消极地切换Q、锁模式的c切割在1.17m的做Nd的vanadate水晶self-Raman激光被使用Cr第一表明<啜class=“a-plus-plus”>4+:YAG。Nd的二晶体<啜class=“a-plus-plus”>3+:YVO4和Nd<啜class=“a-plus-plus”>3+:GdVO4被采用分别地产生激光。与13W的事件泵力量，在1.17m的678mW和852mW的平均产量力量分别地与1.8ns和2ns的切换Q的信封的持续时间被获得。锁模式的重复率分别地象2.3Hz和2.2GHz一样高。根据我们知道，切换Q的信封是最狭窄并且锁模式的重复率是最高目前在这块地里。另外，黄激光输出被使用解放也完成<潜水艇class=“a-plus-plus”>3O<潜水艇class=“a-plus-plus”>5频率加倍水晶。