简介:Tungstendisulfide(WS2)isatypeofanisotropic-layeredcompoundandhasbroadbandsaturableabsorptionfeaturesassaturableabsorbers(SAs).WithWS2-basedSAs,darksolitonsinerbium-dopedfiber(EDF)lasersarefirstobtained.Forthegenerateddarksolitons,thecenterwavelengthismeasuredtobe1530nm,andtherepetitionrateisabout116.5MHz.Aseriesofopticalspectraisexhibited.Theelectricalsignal-to-noiseratioisbetterthan94dB.ResultsinthispaperdemonstratethatWS2-basedSAsarethepromisingSAsforgeneratingdarksolitonsinEDFlasers.
简介:Entangledphotonsarethefundamentalresourceinquantuminformationprocessing.Howtoproducethemefficientlyhasalwaysbeenamatterofconcern.HereweproposeanewwaytoproducecorrelatedphotonsefficientlyfrommonolayerWS2basedonboundstatesinthecontinuum(BICs).TheBICsofradiationmodesinthemonolayerWS2arerealizedbydesigningthephotoniccrystalslab-WS2-slabstructure.Thegenerationefficiencyofcorrelatedphotonpairsfromsuchastructurehasbeenstudiedbyusingarigorousquantummodelofspontaneousparametricdown-conversionwiththeplanewaveexpansionmethod.ItisfoundthatthegenerationefficiencyofcorrelatedphotonpairsisgreatlyimprovedifthesignalandidlerfieldsarelocatedattheBICsdeterminedbytheinversescatteringmatrixofthestructure.Thisisincontrasttotheparametricdown-conversionprocessfortheenhancedgenerationofnonlinearwavesifthepumpfieldislocatedattheBICsdeterminedbythescatteringmatrixofthestructure.Thegenerationrateofthecorrelatedphotonpairscanbeimprovedby7ordersofmagnitudeinsomedesignedstructures.Thegeneratedquantumsignalsaresensitivetothewavelengthandexhibitnarrowedrelativelinewidth,whichisverybeneficialforquantuminformationprocessing.
简介:WereportontheoperationofpassivelyQ-switchedwaveguidelasersat1μmwavelengthbasedonagraphene∕WS2heterostructureasasaturableabsorber(SA).ThegainmediumisacrystallineNd:YVO4claddingwaveguideproducedbyfemtosecondlaserwriting.Thenanosecondwaveguidelaseroperationat1064nmhasbeenrealizedwiththemaximumaverageoutputpowerof275mWandslopeefficiencyof37%.IncomparisonwiththesystemsbasedonsingleWS2orgrapheneSA,thelasingQ-switchedbyagraphene∕WS2heterostructureSApossessesadvantagesofahigherpulseenergyandenhancedslopeefficiency,indicatingthepromisingapplicationsofvanderWaalsheterostructuresforultrafastphotonicdevices.
简介:Liquid-phase-exfoliationtechnologywasutilizedtopreparelayeredMoS2,WS2,andMoSe2nanosheetsincyclohexylpyrrolidone.Thenonlinearopticalresponseofthesenanosheetsindispersionswasinvestigatedbyobservingspatialself-phasemodulation(SSPM)usinga488nmcontinuouswavelaserbeam.ThediffractionringpatternsofSSPMwerefoundtobedistortedalongtheverticaldirectionrightafterthelasertraversingthenanosheetdispersions.Thenonlinearrefractiveindexofthethreetransitionmetaldichalcogenidesdispersionsn2wasmeasuredtobe10-7cm2W-1,andthethird-ordernonlinearsusceptibilityχ(3)10-9esu.TherelativechangeofeffectivenonlinearrefractiveindexΔn2e∕n(2e)oftheMoS2,WS2,andMoSe2dispersionscanbemodulated0.012–0.240,0.029–0.154,and0.091–0.304,respectively,bychangingtheincidentintensities.Ourexperimentalresultsimplynovelpotentialapplicationoftwo-dimensionaltransitionmetaldichalcogenidesinnonlinearphasemodulationdevices.
简介:摘要目的对2例中国云南地区Ⅱ型Waardenburg综合征(Waardenburg syndrome type 2,WS2)患儿进行耳聋基因筛查,探讨其分子生物学致病原因。方法对先证者及家系成员进行病史采集、体格检查、听力学评估及颞骨CT检查。获取外周血提取基因组DNA,采用第二代测序方法对406个耳聋基因编码区的全部外显子及部分内含子和启动子进行检测,对先证者及其父母进行变异位点的Sanger测序验证分析。结果2例患者临床表现为双侧极重度感音神经性聋,双侧虹膜异色,诊断为WS2,二代测序分别检出SOX10基因杂合变异(c.698-2A>C;c.346C>G(p.Q116E)),根据美国医学遗传学与基因组学学会(American College of Medical Genetics and Genomics,ACMG)指南判定为致病性变异,家系内均为自发突变。二代测序结果经Sanger测序证实。结论本研究在中国人群中发现2个SOX10基因变异位点(c.698-2A>C;c.346C>G),丰富了该基因变异的临床表型。
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简介:摘要目的调查2型糖尿病(T2DM)患者中文版低血糖忧虑量表(C-WS)评分情况,分析其危险因素。方法通过便利抽样法选取2016年3月至2018年3月该院收治的T2DM患者300例。采用一般资料调查表、C-WS对患者进行调查,并进行多因素Logistic回归分析。结果300例T2DM患者的C-WS评分1~34分,中位数为11分;其中26~30分占8.67%,31~40分占6.00%,1~10分占46.00%。单因素Logistic回归分析年龄、性别、职业状态、受教育程度、居住方式、医疗付费方式、病程、治疗方式、过去6个月内低血糖发生频率均为T2DM患者C-WS评分的影响因素(均P<0.05)。多因素Logistic回归分析显示,独居、病程、过去6个月内低血糖发生频率>6次均为T2DM患者C-WS评分的独立危险因素(均P<0.05)。结论T2DM患者对低血糖存在明显的担忧、恐惧心理,且居住方式、病程以及过去6个月内低血糖发生频率均对其造成不同程度的影响。临床工作中可能根据患者的自身特点制定个性化干预方案,从而达到缓解患者低血糖忧虑的目的。