简介：AtheoreticalcalculationforthetemperaturedependenceoftheexcitonictransitioninZnSe/ZnCdSequantumwellsisperformed.Theexcitonbindingenergyiscalculatedwithavariationaltechniquebyconsideringthetemperature-dependenceparameters.Ourresultsshowthattheexcitonbindingenergyreduceslinearlywithtemperatureincreasing.Wefindthatthestrainduetolatticemismatchanddifferentialthermalexpansiondecreaseswiththetemperatureincreasing.

简介：摘要：采用化学浴沉积法在以硫酸锌（ZnSO4·7H2O）和自制的硒代硫酸钠（NaSeSO3）作为Zn2+源和Se2-源的化学溶液体系中制备了ZnSe纳米晶薄膜，通过扫描电子显微镜（SEM）、X射线衍射仪（XRD）和分光光度计等测试方法，研究了不同的Zn/Se物质的量比对ZnSe纳米晶薄膜的表面形貌、晶体结构、光学透过率和禁带宽度等物理和光学特性的影响。结果表明，反应液中Zn/Se物质的量比对ZnSe纳米晶颗粒尺寸及致密性影响较大，当nZn/nSe=1:4时制备的ZnSe薄膜有较好的致密性和均匀性。不同Zn/Se物质的量比条件下均制备出(111)取向的立方晶型ZnSe纳米晶薄膜，光学禁带宽度为3.05-3.13eV。当nZn/nSe≤1:4时制备的ZnSe薄膜在450-800 nm波段透过率达75%以上。 

简介：Thestructural,electronic,andelasticpropertiesofZnSe1-xSxforthezincblendestructureshavebeenstudiedbyusingthedensityfunctionaltheory.Thecalculationswereperformedusingtheplanewavepseudopotentialmethod,asimplementedinQuantumESPRESSO.Theexchange-correlationpotentialistreatedwiththelocaldensityapproximationpz-LDAfortheseproperties.Moreover,LDA+Uapproximationisemployedtotreatthe"d"orbitalelectronsproperly.AcomparativestudyofthebandgapcalculatedwithinbothLDAandLDA+Uschemesispresented.Theanalysisofresultsshowconsiderableimprovementinthecalculationofbandgap.Theinclusionofcompositionaldisorderincreasesthevaluesofallelasticconstants.Inthisstudy,itisfoundthatelasticconstantsC11,C12,andC44aremainlyinfluencedbythecompositionaldisorder.Theobtainedresultsareingoodagreementwithliterature.

简介：对Fe∶ZnSe晶体的吸收光谱进行了实验测量和理论计算。通过测量Fe∶ZnSe晶体的透射光谱,给出了Fe∶ZnSe晶体的整体损耗曲线;受限于分光光度计的反射光谱测量范围,无法对该晶体在3μm附近的反射光谱进行直接测量。因此,基于几何光学理论,对晶体的反射光谱进行了理论计算。经对比,计算得到的反射光谱曲线与分光光度计可测区间的反射光谱吻合较好。这样,通过理论计算与实验测量相结合的方法,得到了可信的晶体反射光谱数据。在考虑晶体反射损耗的情况下,计算得到了晶体的吸收光谱曲线,并在此基础上计算了晶体的掺杂浓度,结果与标称掺杂浓度相符。

简介：Thesubbandstructures,distributionsofelectronandholewavefunctions,statedensity,opticalgainspectra,andtransparencycarrierdensityoftheV-grooveZn1-xCdxSe/ZnSequantumwiresareinvestigatedtheoreticallyusingfourbandeffective-massHamiltonian,whichtakesintoaccounttheeffectsofthevalencebandanisotropyandthebandmixing.Thebiaxialstraineffectforquantumwiresisincludedinthecalculation.ThecompressivestrainintheZn1-xCdxSewireregionincreasestheenergyseparationbetweentheuppermostsubbands.Theopticalgainwithxy-polarizedlightisenhanced,whileopticalgainwithz-polarizedlightisstronglydecreased.Thexy-polarizedopticalgainspectrumhasapeakataround2.541Ev,withthetransparencycarrierdensityof0.75×1018　cm-3.Thecalculatedresultsalsoshowthatthestraintendstoincreasethequantumconfinementandenhancetheanisotropyoftheopticaltransitions.

简介：采用水热合成法,通过改变反应条件,实现了三种不同尺寸和形貌ZnSe微球的可控制备。使用X射线粉末衍射(XRD)、扫描电子显微镜(SEM)和紫外-可见光吸收光谱表征其组成、形貌和光学吸收性能。结果表明所有产品均为立方ZnSe结构,具有可见光光响应。利用可见光照射下亚甲基蓝(MB)的降解实验研究不同形貌ZnSe微球的光催化性能。结果表明,具有最小尺寸和复杂形貌的ZnSe微球具有最好的光催化活性。

简介：Thispaperusesfiniteelementmethodtoobtainthethree-dimensionaltemperaturefieldoflaser-inducedtransientthermalgrating(TTG)fortwo-layeredstructureofdiamondfilmonZnSesubstrate.Thenumericalresultsindicatethatuniquetwo-timesheatingprocessisgraduallyexperiencedintheareabetweentwoadjacentgratingstripes.However,thereisalittlechangeforthetemperaturefieldalongthedepthdirectionforthediamondfilmduetoitsgreatthermalconductivity.Itfurtherfindsthatthethicknessofthediamondfilmhasasignificantinfluenceonthetemperaturefieldindiamond/ZnSesystem.Theresultsareusefulfortheapplicationoflaser-inducedTTGtechniqueinfilm/substratesystem.

简介：在液相环境中，利用纳秒（ns）脉冲激光器轰击消融铬掺杂ZnSe（Cr^2＋：ZnSe）微米颗粒，制备出Cr^2＋：ZnSe纳米粒子，扫描电镜以及X射线衍射检测，结果显示，制备所得的粒子为平均尺寸为50nm的ZnSe闪锌矿结构纳米粒子。基于Cr^2＋：ZnSe纳米粒子，观察到中心波长为2180nm、阈值为0．4mJ／pulse的随机激光效应。相比于Cr^2＋：ZnSe晶体激光器，纳米粒子随机激光的中心波长发生了约170nm的蓝移，Cr^2＋：ZnSe纳米粒子的光致发光寿命也比Cr^2＋：ZnSe晶体要短。