简介：Progressesinphotovoltaictechnologiesoverthepastyearsareevidentfromthelowercosts,therisingefficiency,tothegreatimprovementsinsystemreliabilityandyield.Cumulativeinstalledpoweryearlygrowthswereonanaveragemorethan40%intheperiodfrom2007to2016andin2016,theglobalcumulativephotovoltaicpowerinstalledhasreached320GWp.Thelevel0.5TWpcouldbereachedbefore2020.Theproductionprocessesinthesolarindustrystillhavegreatpotentialforoptimizationbothwaferbasedandthinfilmtechnologies.Trendsfollowingfromthepresenttechnologylevelsarediscussed,alsotakingintoaccountotherpartsofphotovoltaicsystemsthatinfluencethecostofelectricalenergyproduced.Presentdevelopmentsinthethreegenerationsofphotovoltaicmodulesarediscussedalongwiththecriteriafortheselectionofappropriatephotovoltaicmodulemanufacturingtechnologies.Thewaferbasedcrystallinesilicon(csilicon)technologieshavetheroleofworkhorseofpresentphotovoltaicpowergeneration,representingmorethan90%oftotalmoduleproduction.Furthertechnologyimprovementshavetobeimplementedwithoutsignificantlyincreasingcostsperunit,despitethenecessarilymorecomplexmanufacturingprocessesinvolved.Thetandemofc-siliconandthinfilmcellsisverypromising.Durabilitymaybealimitingfactorofthistechnologyduetothedependenceoftheproducedelectricitycostonthemoduleservicetime.

简介：Inrecentyears,topologicalinsulatorshavearousedtheattentionofagreatnumberofscientistsduetotheiruniqueelectronicstructuresandpeculiarphysicalproperties.Triggeredbythesimilarelectronicstructuresasgraphene,thebroadbandnonlinearabsorptionpropertiesoftopologicalinsulatorswereinvestigated.Moreover,themode-lockedorQ-switchedfiberlasersbasedontopologicalinsulatorswererealizedforbroadbandoperatingwavelength.Here,wepresentanoverviewofthepreparation,transferring,linearandnonlinearopticalproperties,andtheirapplicationsoftopologicalinsulatorsinpulsedfiberlasers.Thepulsedfiberlaserstowardsmidinfraredregimeshavebeenproposed.

简介：Ozoneisagreenhousegas.Ozoneabsorptioncrosssectionshavebeenreportedwithdiscrepanciesandinconsistencies.Inthispaper,simultaneouseffectsoftheopticalpathlengthandtemperaturevariationsonozonegasabsorptioncrosssectionsareinvestigatedatdifferentwavelengths.HITRAN2012,thelatestavailablelinelistonspectralcalc.comsimulator,isusedinthisstudytosimulateozonegasabsorptioncrosssectionsinrelationtothesimultaneouseffectsoftheopticalpathlengthandtemperatureatthewavelengthsof603nmand575nm.Resultsobtainedforgascellswiththeopticalpathlengthfrom10cmto120cmshowthatthedecreaseintemperaturesfrom313Kto103Kresultsintheincreaseinozonegasabsorptioncrosssections.Atwavelengthsof603nmand575nm,thepercentageincreaseofozonegasabsorptioncrosssectionsis1.22%and0.71%,respectively.Resultsobtainedinthisstudyshowthatinthevisiblespectrum,atconstantpressure,ozonegasabsorptioncrosssectionsaredependentonthetemperatureandwavelengthbutdonotdependontheopticalpathlength.Analysisinthisworkaddressesdiscrepanciesinozonegasabsorptioncrosssectionsinrelationtothetemperatureinthevisiblespectrum;thus,theresultscanbeappliedtogetoptimalconfigurationofhighaccuracyozonegassensors.