简介：英国防务评估研究署正在研制一种由计算机控制的电子步枪，英国《星期日泰晤土报》最近披露了这种新型武器的设计情况。

简介：Photoconductivesemiconductorswitches(PCSSs)arewidelyusedinhighpowerultra-widebandsourceapplicationsandprecisesynchronizationcontrolduetotheirhighpowerlow-jitterhigh-repetition-frequency.Inthisletter,a14-mmgapsemi-insulatingGaAsPCSSbiasedunder20kVistriggeredbya1064-nmlaserwitharepetitionfrequencyof30Hz.Althoughthetriggerconditionisgreaterthanthethresholdofthelock-oneffect,thehighgainmodeisnotobserved.TheresultsindicatethatthehighgainmodeofthePCSSisquenchedbydecreasingtheremnantvoltageofpulsedenergystoragecapacitor.

简介：Thisletterpresentsalowcostsolutionforwavelengthdivisionmultiplexedorthogonalfrequencydivisionmultiplexedpassiveopticalnetwork(WDM-OFDM-PON)withwidelytunableopticalfilterandlinearsmallform-factorpluggable(SFP)module.With9-nmtunablerangefrom1551to1560nm,thetunablefiltercansupportupto10-channel100-GHzspacingWDMPONsystem.Alinearavalanchephotodiode(APD)basedSFP+moduleisdesignedforopticalOFDMsignaldemodulation,whichcanprovidebetterreceiverperformancecomparedwithlimitingAPDmodule.Experimentalresultsshowthat～34dBpowerbudgetcanbeachievedin4×5-GbpsWDM-OFDM-PONsystem,whichcansatisfythetransmissionrequirementsofnextgenerationPONsystem.

简介：Adiode-end-pumpedelectro-optic(EO)Q-switchedgreenlaseroperatingattherepetitionrateof20kHzisreported.AblockofLa_3Ga_5SiO_(14)(LGS)singlecrystalisusedasaQ-switchandthetypeⅠphase-matchingLiB_3O_5(LBO)isusedasthenonlinearcrystalinthesecondharmonicgeneration.The2.3-Waveragepowerof532-nmgreenlaserisobtainedattherepetitionrateof20kHzwiththepulsewidthasshortas10ns.Whentheoutputpowerisabout1.5W,themeasuredpowerfluctuationislessthan1.4%(root-mean-square,RMS)withthebeamqualityfactorofM~2<2inbothorthogonaldirections.