SNLO_Help帮助文件

整理文档很辛苦,赏杯茶钱您下走!

免费阅读已结束,点击下载阅读编辑剩下 ...

阅读已结束,您可以下载文档离线阅读编辑

资源描述

SNLOHelpArleeSmithOctober13,20091AboutSNLOSNLOiswrittenandmaintainedbyArleeSmithatAS-PhotonicsinAlbuquerque,NewMexico.ItiswritteninAPLprogramminglanguage.Itiscon-tinuouslyupdatedwiththelatestversionavailableonlineat leSNLO.PDFthatisinyourSNLOfolder,alsoavailableonlineat les/SNLO.pdfShouldyouwishtoreferenceSNLOinapublicationpleaseuse:`SNLOnonlinearopticscodeavailablefromA.V.Smith,AS-Photonics,Albuquerque,NM'Comments,questions,andsuggestionsarewelcome.Sendthemtomeat:arlee.smith@as-photonics.comAll*.DAT lesinSNLOdirectoryareoutputdata lesandmaybedeletedtorecoverdiskspace.Additionalcrystalinformationisavailableinthe135pagebibliographyCRYSTALS.PDF(intheSNLOdirectory,andavailableonline),andfromthe leBetan2.pdfwhichincludestablesofreportedtwo-photonabsorptioncrosssectionsandnonlinearre-fractiveindexcoecients.This lemaybefoundinyourSNLOfolder.2Functions2.12D-mix-LP2D-mix-LPissimilartoPW-mix-LPexceptithan-dlesthefullspatialpro lessoitcanrealisticallymodelcircularorellipticalbeamswithGaussianorSupergaussiantransversepro les.Itincludesdi rac-tion,birefringentwalko ,displacedbeams,etc.forpulsedorcwlight.Thelightisassumedtobemonochromatic,andthepulsesareassumedtobelongenoughthatgroupvelocitye ectsareunim-portant.Maxwell'sequationsareintegratedusingsplit-stepmethodstogivetruedi ractivecalcula-tions.Modelingmethodsaredescribedindetailinpapers\Phasedistortionsinsum-anddi erence-frequencymixingincrystals,JOSABvol.12p.49(1995),and\Comparisonofanumericalmodelwithmeasuredperformanceofaseeded,nanosecondKTPopticalparametricoscillator,JOSABvol.12p.2253(1995).Thesepapersareavailableonlineat(seeReadme.txt leaboutmemoryallocation).For12Mb,thegridcanbeaslargeas128128,for180Mbitcanbeupto512512.A3232gridisusuallyadequate.IsuggestyouusethemuchfasterPW-mix-LP rstto ndreasonablevaluesfortheinputparameters.Outputsincludebeamtiltsinthewalko direction(Tilt),time-dependentM2valuesinthewalko direc-tionandperpendiculartoit(M-wandM-pbuttons),timeintegratedM2values(writtenattopofplotsoftimedependentM2),andwavefrontcurvatureattheplanespeci edbythepropagationdistanceinputparameter.Youshouldmakesuretheseresultsareconvergedbyincreasingthegriddensitybyfactorsoftwountiltheanswersstabilize.Usuallyagridof3232or6464isadequate.Phasesareplottedo setby+sotherangeis(0to2)insteadof(to).Theinputpulses(ifnotcw)areallcenteredatt=0.Runsstartatt=0andprogresstolatertime.Timest0arenotmodeledbecauseofthesymmetryaboutt=0.Theresultsarewrittentoascii les*INT.DATand*PH.DAT,wherethe*INT les(*PH les)areirradiance(phase)outateachtimestepwithcolumnsx,y,irr(t1),irr(t2),....Theascii lesSIGBEAM.DAT,IDBEAM.DATandPMPBEAM.DATcontaintime,power,phase,M2x,M2y,X-curvature,Y-curvature,andX-tiltincolumns18(whereXisthewalko direction).Theuenceiswrittentotheascii leFLUENCE.DATwithcolumnsx,y,signaluence,idleruence,pumpuenceatthepropagationdistancespeci ed(from1exitfaceofcrystal).FLUENCF.DATistherelativefar elduenceangulardistributionwithcolumnsx-angle,y-angle,signaluence,idleruence,pumpuence.Actualxandyangles(inradians)arefoundbymultiplyingx-angleory-anglebythewavelength(inmeters)ofthesignal,idler,orpumpwave.ThesedistributionsareFouriertransformsofthe eldsatthecrystalexitface.Noncollinearphasematchinginthecriticalplanecanbefakedbyusingthewalko parameter.Forexam-ple,ifthesignal'struewalko angleis50mradandyouwanttopropagatethepumpalongthisdirec-tion,youwouldspecify50mradforboththesignalandpump.Youmustthencompensatebyadjustingtheidlerwalko tobe50idler=pump.Inotherwords,fakewalko mustbecompensatedtomaintainphasematch,butrealwalko isnotcompensated.Ofcourse,thetiltswillnotreecttheactualvaluesforthefakewalko butwillbethedeviationfromtheinputbeamtilt.ThelastusedinputsetissavedinMIX.SFsoifyouwouldliketosavethosesettingsforlaterrecall,copyMIX.SFtoanother lenametostore.Copythe lebacktoMIX.SFtorestore.2.22D-mix-SP2D-mix-SPmodelssingle-passmixingwithdi rac-tion,birefringentwalko ,groupvelocitywalko ,andgroupvelocitydispersion.ThisisaslowmemoryhogsotrytoselectthebestvaluesforthetimeandspatialgridsusingthefasterfunctionsPW-mix-SP,PW-mix-LP,and2D-mix-LPbeforerunningit.Themaximumsizesofthespatialandtemporalgridsde-pendontheamountofmemoryallocatedtoSNLO(seeReadme.txt leaboutmemoryallocation).A3232128gridrequires35MballocatedtoSNLO.Thisshouldbeadequateformostsituations.ThecalculationisbasedonintegratingMaxwell'sequationsusingsplit-stepFFTmethodstogiveaccu-ratedi ractiveandgroupvelocitysimulations.Meth-odsaredescribedinpapers\Numericalmodelsofbroadbandwidthnanosecondopticalparametricos-cillators,JOSABvol.16p.609(1999);\Phasedis-tortionsinsum-anddi erence-frequencymixingincrystals,JOSABvol.12p.49(1995);and\Com-parisonofanumericalmodelwithmeasuredperfor-manceofaseeded,nanosecondKTPopticalpara-metricoscillator,JOSABvol.12p.2253(1995).Thesepapersareavailableonlineat

1 / 11
下载文档,编辑使用

©2015-2020 m.777doc.com 三七文档.

备案号:鲁ICP备2024069028号-1 客服联系 QQ:2149211541

×
保存成功