简介:Wereportonanoveldibenzothiophene-basedtwo-photonfluorescentprobeforselectivenuclearbioimaging,whichcontainsbilaterallysymmetricalpyridineringsconnectedbyacentralconjugated-bridgedibenzothiophene.Thisprobepossessesalargetwo-photonabsorptioncross-sectionof471GM,yieldsa25-foldenhancementofthefluorescencetitration,andastrongerphotostabilityfornucleilabelingthanexistingprobes.Thereal-timeobservationperiodisaminimumof1800sunderafemtosecondlaserexcitation,whichissignificantlylongerthanthatof40,6-diamidino-2-phenylindole.Theaboveresultsconfirmthatthisnovelmoleculeisasuitabletwo-photonfluorescentprobeforapplicationtonuclearbioimagingincells.
简介:Wereportanopticallyaddressedliquidcrystallightvalve,ahome-madedevicethathassolvedtheproblemoflowtransmittancecausedbyopaqueelectrodesinpresenttransmissivespatiallightmodulators.Theoperatingcharacteristicofthelightvalveisanalyzed.Theoptimumdrivingvoltageofthisdeviceis27Vat300Hz,asdeducedfromtheequivalentelectricmodel.Itstransmittancereaches80%anditscontrastisapproximately40:1.Itsdynamicperformance,especiallyitsabilitytoobscurelaserlightatprogrammedlocations,isdemonstrated.Theresultsareingoodagreementwiththedesiredshape,whichindicatesthatourlightvalveperformsverywell.
简介:Thereisatradeoffbetweenthequantumefficiencyandthespectralresponselinewidthinresonant-cavityenhanced(RCE)photodetectors.Recentlyanewtypeofphotodetectorstructurehasbeenproposed,whichutilizesaninclinedmirrorinathree-mirrorcavity.Itdecouplesthequantumefficiencyandthespectralresponselinewidthandhashighresponsespeed,highquantumefficiency,andnarrowlinewidthsimultaneously.Theanalysisresultindicatesthatthelinewidthof0.8nmandquantumefficiencyhigherthan70%canbeachievedonthisdevice.Fora30×30μm2device,themaximumbandwidthapproaches23GHz.