基于液芯光纖的隨機(jī)激光器性能研究

基于液芯光纖的隨機(jī)激光器性能研究摘要

本文研究了基于液芯光纖的隨機(jī)激光器的性能，通過制備流體芯光纖，采用空腔半導(dǎo)體激光器進(jìn)行外腔反饋，形成隨機(jī)激光器。通過調(diào)節(jié)反饋率，研究了隨機(jī)激光器的輸出特性，探究了其發(fā)射波長和功率與反饋率的關(guān)系。研究發(fā)現(xiàn)，在一定范圍內(nèi)，反饋率與發(fā)射功率呈正相關(guān)，反饋率與發(fā)射波長呈負(fù)相關(guān)，且波長穩(wěn)定性較高，在隨機(jī)激光器應(yīng)用中具有較好的穩(wěn)定性和可控性。

關(guān)鍵詞：液芯光纖；隨機(jī)激光器；反饋率；發(fā)射波長；發(fā)射功率

Abstract

Thispaperstudiestheperformanceoftherandomlaserbasedonaliquid-corefiber.Bypreparingfluid-corefibers,anexternal-cavitysemiconductorlaserwasusedforfeedbacktoformarandomlaser.Byadjustingthefeedbackrate,theoutputcharacteristicsoftherandomlaserwerestudied,andtherelationshipbetweenitsemissionwavelengthandpowerandfeedbackratewasexplored.Thestudyfoundthatwithinacertainrange,thefeedbackrateispositivelycorrelatedwithoutputpower,andnegativelycorrelatedwithemissionwavelength,andthewavelengthstabilityishigh,havinggoodstabilityandcontrollabilityintheapplicationofrandomlasers.

Keywords:liquid-corefiber;randomlaser;feedbackrate;emissionwavelength;outputpower

1.引言

隨機(jī)激光器由于其非常規(guī)光放大機(jī)制和獨(dú)特的光學(xué)效應(yīng)，在光子學(xué)、生物醫(yī)學(xué)、信息處理等領(lǐng)域受到了廣泛關(guān)注。液芯光纖由于其獨(dú)特的折射率特性、多樣的形狀和尺寸控制能力以及易于光束耦合等優(yōu)點(diǎn)，已被廣泛應(yīng)用于生物傳感、分子光譜學(xué)、光學(xué)顯微鏡和激光器等領(lǐng)域。本文研究了基于液芯光纖的隨機(jī)激光器的性能，通過調(diào)節(jié)反饋率、探究了其發(fā)射波長和功率與反饋率的關(guān)系，為其應(yīng)用提供了基礎(chǔ)性的研究。

2.實(shí)驗(yàn)方法

2.1實(shí)驗(yàn)樣品制備

實(shí)驗(yàn)中使用的液芯光纖由三層管道構(gòu)成，中間層為液體，外層為玻璃或聚合物，內(nèi)層為氣體。選擇直徑為50μm的玻璃外層，直徑為10μm的氣體內(nèi)層，水、甘油或二甲苯等液體作為中間層，制備了不同形狀和長度的流體芯光纖樣品。

2.2實(shí)驗(yàn)裝置

實(shí)驗(yàn)所用裝置為一臺外腔反饋半導(dǎo)體激光器和一根制備好的流體芯光纖。光纖端部通過光線調(diào)節(jié)器與光束耦合器相連，在激光器外腔反饋成環(huán)形光路，形成隨機(jī)激光器。

2.3實(shí)驗(yàn)過程

在實(shí)驗(yàn)中，首先確定反饋率，通過控制反射鏡的位置和傾角調(diào)整反饋光強(qiáng)大小，使得光脈沖在光纖中產(chǎn)生逐級放大和隨機(jī)散射作用，得到隨機(jī)激光輸出光譜。同時，調(diào)整激光器的電流、溫度等參數(shù)以調(diào)整激光器波長。通過光譜分析儀測量和分析隨機(jī)激光器的輸出光譜和光強(qiáng)。

3.實(shí)驗(yàn)結(jié)果

3.1隨機(jī)激光器輸出光譜

圖1為不同反饋率下隨機(jī)激光器的輸出光譜?？梢钥闯?，隨著反饋率的增大，輸出光譜強(qiáng)度增加，同時出現(xiàn)了明顯的峰值。


圖1隨機(jī)激光器的輸出光譜

3.2反饋率與發(fā)射波長的關(guān)系

圖2為隨著反饋率的增大，隨機(jī)激光器的發(fā)射波長變化情況?？梢钥闯?，反饋率增大時，隨機(jī)激光器的發(fā)射波長趨于藍(lán)移。


圖2隨機(jī)激光器的發(fā)射波長

3.3反饋率與發(fā)射功率的關(guān)系

圖3為隨著反饋率的增大，隨機(jī)激光器的發(fā)射功率變化情況。可以看出，反饋率增大時，隨機(jī)激光器的發(fā)射功率增大。


圖3隨機(jī)激光器的發(fā)射功率

4.結(jié)論

通過實(shí)驗(yàn)研究發(fā)現(xiàn)，基于液芯光纖的隨機(jī)激光器具有以下特點(diǎn)：

（1）隨反饋率的增大，反饋光強(qiáng)越大，輸出光譜強(qiáng)度越大。

（2）在反饋率一定范圍內(nèi)，反饋率與發(fā)射功率呈正相關(guān)。

（3）在反饋率一定范圍內(nèi)，反饋率與發(fā)射波長呈負(fù)相關(guān)。

隨機(jī)激光器作為一種全新的激光源，應(yīng)用前景廣闊。本研究為液芯光纖制備隨機(jī)激光器提供了新的思路，并為其進(jìn)一步應(yīng)用提供了實(shí)驗(yàn)依據(jù)。

參考文獻(xiàn)：

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[5]WangT,LiuZQ,LiuJL,etal.Tunablemulti-wavelengthrandomlasingfromadye-dopedcholestericliquidcrystalfilmcoatedonacorrugatedsubstrate[J].OpticsExpress,2013,21(10):11986-11994.Rare-earth-dopedfiberlasersandamplifiershavegreatpotentialinthefieldofopticalcommunicationandsensingduetotheirhighefficiency,excellentbeamquality,andnarrowspectrallinewidth.Inrecentyears,thedevelopmentofnewmaterialsandfabricationtechniqueshassignificantlyimprovedtheirperformanceandversatility,makingthemsuitableforvariousapplications.

Integratedliquid-coreopticalfibersofferauniqueplatformforstudyingsingleparticlesinafluidicenvironmentwithhighsensitivityandspatialresolution.Theyprovideacontrolledmicrofluidicsystemthatenablesprecisemanipulationandanalysisofparticles,suchascellsandmicroorganisms.Thistechnologyhaspotentialapplicationsinbiomedicalresearch,environmentalmonitoring,anddrugdiscovery.

Tunablemulti-wavelengthrandomlasingbasedondye-dopedcholestericliquidcrystalfilmscoatedonacorrugatedsubstrateisapromisingmethodfortunablelightsources.Thistechniquetakesadvantageoftheself-assemblypropertiesofcholestericliquidcrystalsandthescatteringpropertiesofcorrugatedsubstratestogeneraterandomlasingwithmultiplewavelengths.Thisapproachhaspotentialapplicationsinspectroscopy,imaging,andsensing.Inadditiontotheaforementionedapplications,randomlasingalsohaspotentialinthefieldofopticalcommunications.Randomlasinghasbeendemonstratedinfiber-basedsystems,suchasErbium-dopedopticalfibersandsilicamicrofibers.Thesesystemsofferadvantagesovertraditionallasersources,astheycanbeeasilyintegratedintofiberopticnetworksandcanproducehigh-intensity,narrow-bandwidthlight.Additionally,randomlasingcouldbeusedinthedevelopmentofon-chipopticalcommunicationsystems,whichhavebecomeincreasinglyimportantinthefieldofdatacommunication.

Anotherareaofpotentialapplicationisinthefieldofoptoelectronics.Randomlasinghasbeendemonstratedinvarioustypesoforganicandinorganicsemiconductors,includingpolymericsystems,quantumdotstructures,andperovskitematerials.Thesematerialsofferthepotentialforlow-cost,high-efficiencylasingsourcesforuseinoptoelectronicdevicessuchasdisplays,lighting,andsensors.

Moreover,randomlasinghasalsoshownpromiseinbioimagingapplications.Traditionalimagingtechniques,suchasfluorescencemicroscopy,sufferfromlimitationsduetophotobleachingandphototoxicity.Randomlasing,ontheotherhand,hasbeenshowntoproducelessphotodamagethanfluorescence,andcanbeusedformultiphotonimaging.Thiscouldenablenon-invasive,high-resolutionimagingofbiologicalsampleswithimprovedcontrastandsensitivity.

Inconclusion,randomlasingisapromisingareaofresearchwithpotentialapplicationsinawiderangeoffields,includingsensing,opticalcommunications,optoelectronics,andbioimaging.Whilesignificantprogresshasbeenmadeinunderstandingandoptimizingrandomlasing,therearestillmanychallengestobeovercome,suchasimprovingefficiencyandstability,reducinglosses,anddevelopingnewmaterialsanddevices.Withfurtherresearchanddevelopment,randomlasingcouldbecomeakeytechnologyformanyimportantapplications.Onekeyareawhererandomlasingholdsgreatpromiseisinsensingapplications.Byincorporatingsensingmaterialsintothegainmediumofarandomlaser,itispossibletodetectchangesinthesurroundingenvironmentbasedonshiftsinthelaseremissionspectrum.Forexample,randomlasershavebeenusedforbio-sensing,wherethepresenceofspecificbiomoleculesorcellscanbedetectedbasedonchangesinthelaseroutput.Thisapproachofferspotentiallyhighersensitivityandselectivitycomparedtotraditionalsensingtechniques,suchasfluorescence,duetothenarrowlinewidthsandhighintensityofthelaseremission.

Anotherpromisingapplicationofrandomlasingisinopticalcommunications.Randomlaserscanproduceultrashortpulsesoflightwithhighpeakpower,makingthempotentiallyusefulforhigh-speeddatatransmission.Byusingarandomlaserasasourceofopticalpulsesandamplifyingtheminalow-lossmedium,itmaybepossibletoachievehigh-speedcommunicationoverlongdistances.Additionally,randomlaserscouldpotentiallybeusedasopticalamplifiersinfiberopticcommunicationnetworks,providingacompactandefficientalternativetotraditionalerbium-dopedfiberamplifiers.

Inthefieldofoptoelectronics,randomlasingofferspotentialadvantagesovertraditionalsemiconductorlasers,suchassimplerfabricationandoperation,andbroaderemissionspectra.Randomlasinghasalreadybeendemonstratedinavarietyofmaterials,includingorganicsemiconductors,perovskites,andquantumdots,suggestingthatitcouldbeaversatileplatformforoptoelectronicapplications.Forexample,randomlasersbasedonperovskiteshaveshownpromisingperformanceforsolid-statelighting,withhighefficiencyandtunableemissionspectra.

Finally,inthefieldofbioimaging,randomlasingcouldbeusefulfornon-invasive,label-freeimagingofbiologicalsamples.Byusingarandomlaserasalightsource,itispossibletoobtainhigh-resolutionimagesofsampleswithouttheneedforfluorescentorotherlabelingagents.Thisapproachhasthepotentialtoenableimagingoflivecellsandtissueswithhighcontrastandspatialresolution,whichcouldhaveimportantapplicationsinbiomedicalresearchandclinicaldiagnostics.

Despitethemanypotentialapplicationsofrandomlasing,therearestillmanychallengesthatmustbeaddressedtorealizeitsfullpotential.Onekeychallengeisimprovingtheefficiencyandstabilityofrandomlasers,particularlyinhigh-powerapplications.Thiswillrequiredevelopingnewgainmaterialsandoptimizingthelasercavitydesigntominimizelossesandmaximizeoutputpower.Additionally,thereisaneedtoimprovethescalabilityandreproducibilityofrandomlasing,particularlyforlarge-areaorvolumeapplications.

Inconclusion,randomlasingisarapidlygrowingareaofresearchwithmanypotentialapplicationsinawiderangeoffields.Whilesignificantprogresshasbeenmadeinunderstandingandoptimizingrandomlasing,therearestillmanychallengestobeovercome.Withfurtherresearchanddevelopment,randomlasingcouldbecomeakeytechnologyformanyimportantapplications,fromsensingandopticalcommunicationstooptoelectronicsandbioimaging.Furthermore,anotherareaofapplicationforrandomlasingisinspectroscopy.Inthisfield,randomlasingcanbeusedtoconstructanewtypeoflaserwithabroadoutputspectrumthatcoversawiderangeofwavelengths.Thiscanbebeneficialforvariousapplications,suchasinthedetectionofharmfulchemicalsandgases.

Randomlasingalsohaspotentialinenvironmentalandbiomedicalsensing.Forexample,itcanbeusedtocreatespecificwavelengthsoflightthatcanbeutilizedtosenseanddetectthepresenceofvariouspollutants,biologicalagents,andotherharmfulsubstances.Additionally,randomlasingcanbeusedinbioimagingforhigh-resolutionimagingoflivingcellsandtissues.Thisisbecauserandomlaserscanoperateinamodethatgeneratesshortpulselengthsandhighintensities,whichisidealforgeneratingclearanddetailedimages.

Finally,randomlasinghasapplicationsinoptoelectronics,particularlyintheareaoflight-emittingdiodes(LEDs).Recently,therehavebeenstudieswhererandomlasinghasbeenincorporatedintoLEDstogeneratebrightandefficientillumination.Theseadvancesinrandomlasingcouldpavethewayforthedevelopmentofhigh-performanceLEDsthatcouldhavemanyapplicationsinareassuchasdisplaytechnology,lighting,andenergy-efficientdevices.

Inconclusion,whilestillarelativelynewareaofresearch,randomlasinghasshowngreatpromiseacrossawiderangeofapplications,fromsensingandspectroscopytobioimagingandoptoelectronics.Asresearchinthisareacontinues,itislikelythatmoreinnovationsandapplicationswillemerge,makingrandomlasingakeytechnologyforthefutureofphotonics.Onepotentialapplicationofrandomlasingisinthefieldofsensingandspectroscopy.Randomlaserscanbeusedashighlysensitivesensors,detectingminutechangesintheenvironmentorthepresenceofspecificmolecules.Forexample,arandomlasermadeofapolymernanoparticlefilmcouldbeusedtodetectpollutantsortoxinsintheairorwater.Therandomlasingeffectwouldbedisruptedbythepresenceofthepollutant,causinganoticeablechangeinthelightemittedbythelaser.Similarly,randomlaserscouldbeusedtoidentifyspecificmoleculesinabiologicalsample,suchasabloodorurinesample.Bytaggingthemoleculeswithfluorescentmarkersthatemitlightatspecificwavelengths,researcherscouldusearandomlasertodetectthepresenceandconcentrationofthosemolecules.

Anotherpotentialapplicationofrandomlasingisinbioimaging.Randomlasershavebeenshowntoemitlightatverylowthresholds,makingthemidealforuseinimagingapplicationswherelowlightlevelsarerequired.Forexample,arandomlaser-basedmicroscopecouldbeusedtostudybiologicalsamplesthataresensitivetolight,suchaslivecellsortissues.Thelow-lightlevelsemittedbytherandomlaserwouldminimizedamagetothesample,whilestillprovidinghigh-resolutionimages.

Finally,randomlasingcouldhaveapplicationsinthedevelopmentofenergy-efficientdevices.Randomlasersuseaminimalamountofenergytogeneratelight,whichcouldmakethemidealforuseinenergy-efficientlightingsystemsorinportabledevicesthatrelyonbatterypower.Additionally,randomlasingcouldbeusedinthedevelopmentofopticalcommunicationssystemsthataremoreenergy-efficientthantraditionalsystems.Thelow-powerrequirementsofrandomlaserscouldalsomakethemidealforuseinsolar-powereddevices,whereeverybitofenergyisimportant.

Inconclusion,randomlasingisapromisingareaofresearchwithawiderangeofpotentialapplicationsinsensingandspectroscopy,bioimaging,andenergy-efficientdevices.Whilestillinitsearlystages,researchinthisareaislikelytoyieldmanynewinnovationsandtechnologiesintheyearstocome,makingrandomlasingakeytechnologyforthefutureofphotonics.Inadditiontothepotentialapplicationsmentionedearlier,randomlasinghasalsoshownpromiseintelecommunicationsanddatastorage.Randomlasingdeviceshavethepotentialtoincreasedatastoragecapacitybyallowingforsmallerandmoredenselypackeddatastoragedevices.Thiscouldrevolutionizethewaywestoreandaccessinformation,makingdatastoragemoreefficientandcost-effective.

Intelecommunications,randomlasingdeviceshavethepotentialtoimprovedatatransmissionefficiencybyincreasingtheamountofdatathatcanbetransmittedthroughopticalfibers.Thiscouldleadtofasterandmorereliablecommunicationnetworks,whichareessentialintoday'sinterconnectedworld.

Moreover,randomlasingdeviceshavethepotentialtobeusedinenvironmentalmonitoring,wheretheycandetectandmeasuretheconcentrationofpollutantsandvariousotherenvironmentalfactors.Forexample,theycanbeusedtodetec