Work at Argonne National Laboratory was funded by the Department of Energy, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357, which also funds Argonne's Center for Nanoscale Materials (CNM) where the patterning of the BSCCO mesa was performed. We thank R. Divan and L. Ocola for their help with sample fabrication.

1.样品用于涂料的制备注:如果可能，从样品的表面去除所有有机物污染以热成像。任何这样的污染可能与沉积的EuTFC膜反应并改变其发光响应，在所得到的热图像引起依赖于位置的伪像。这是与用Au的表面电极，其倾向于吸引从大气中有机污染物的样品特别重要的。除去同时坐在样品表面上的任何颗粒或灰尘，因为这些可能会导致伪像也。笔者建议采用以下步骤: <ol><li>使诸如超导桥或电阻装置的电流和电压连接，以在样品上的装置（ 例如引线键合，涂上使用导电环氧树脂等连接）清洗它在用于薄膜涂层制备之前 ，因为这些步骤可能引入污染w ^HICH应涂层前被去除。如果可能，请使用Au线，因为这将使它更容易在样品连接到低温恒温器的膜已经沉积之后。 （参见下面的步骤4.6）。 </li><li>清洗，在100％丙酮中的样品中的15秒的超声浴。 </li><li>而不使样品干燥，清洁它在100％异丙醇中进行5秒的超声浴中。 </li><li>使用氮气枪吹样品干燥。 </li><li>如果可能的话，则清洁使用氧等离子体灰化掉所述样品表面上的任何残留的有机残基。要做到这一点，使用100 W，22 立方厘米 /秒的O 2流量和160毫乇的气体压力的等离子体功率，60秒。为了避免样品的再污染，在该步骤之后尽快沉积EuTFC涂层。 </li></ol> 2.制备涂料体系的EuTFC沉积<ol><li>使用由从不锈钢储物柜制成的专门建造的船20×10×10mm的3大小时（LXWXH）的升华的源钢铁箔包封锰铜的电阻丝的线圈10，用于操作在约100 - 200℃。通过浸泡在丙酮中，因为这些将不利地新的膜的性能影响溶解从船上EuTFC的任何熔化的残余物。 </li><li>冲洗异丙醇船。 </li><li>允许船在进行EuTFC加载到它之前在空气中完全干燥。 </li><li>从水蒸汽和轻保护EuTFC粉末被存储，同时它。用玛瑙研钵，以消除任何可见肿块彻底粉碎EuTFC粉末。 注意:即使当粉末从水蒸气的保护，但它仍然可以结晶成100微米直径或更大的块状物。这些必须去除，因为它们将导致严重的非均匀膜时升华，导致在热图像伪影。 </li><li>安装样品支架和升华源在所述真空涂层系统，使得样品位于大约10mm源舟正上方（合适地取向的晶体厚度传感器，用于监控沉积速率）。连接源舟加热器导致其相关的真空馈通。 </li><li>填充源舟约2/3满大约0.2克地面EuTFC粉末。 </li><li>安装样品倒置直接在源舟以上（以确保沉积的膜的均匀性），优选使用双面胶带或粘点，而不是真空润滑脂，它可能污染膜。 </li><li>以减少样品表面和EuTFC粉末在大气中（特别是水蒸气）的曝光尽快使用旋转泵开始将淀积室抽真空。 </li></ol> 3.沉积EuTFC薄膜由热升华<ol><li>沉积室泵送至3×10 -5毫巴或更小，优选地使用涡轮分子泵。 </li><li>程序的体厚度监控仪来读取1.50克/厘米3的膜密度。 </li><li>应用0.5 W的功率到源舟加热器，轻轻地暖源，直到EuTFC开始升华。这将需要2 - 3分钟的厚度监测开始阅读一个明显的沉积速率。 </li><li>调整加热器功率来维持6的沉积速率 - 7纳米/分钟。只作小，速度慢的调整，因为沉积速率通常需要1 - 2分钟，在输入功率的变化做出反应。 注:小船温度足以在该结构中以沉积大于10nm /分钟可能导致粉末在船熔化，大大减少其表面积，因此升华速率。更重要的是，过多的舟的温度可能从化学上改变EuTFC并且因此强烈地降低其发光的热灵敏度。 </li><li>膜沉积的200纳米（通过厚度监视器读取）之后，关闭电源源。 （±20nm的是可以接受的在这里，虽然厚度在该范围之外显著将导致较低的胶片感光度）。 </li><li>厚度监视器上的读数达到零之后，排气腔室中，用干燥的氮气。取出后，在真空干燥器中不透光容器尽快避光和水蒸汽的样品，通过存储。 注意:这将分别防止EuTFC薄膜的漂白和化学降解。 </li></ol> 4.安装在测量低温恒温器样品<ol><li>放置真空润滑脂的斑点在中心低温恒温器样品台大约1-2毫米的直径。使用的样品台，其包括具有圆形顶面15毫米的直径铜冷手指。 注意:这是足够的尺寸以确保阶段和当样品被向下压平在其顶部上的样品之间的强热接触。 </li><li>如果样品基体是导电，通过放置一个10微米的Mylar片上的润滑脂的顶部从舞台隔离它，和一个第二大小同样在聚酯薄膜的顶部ð团块。 注:作者发现，最好是采用脂具有相对高的粘度（ 例如，有机硅系高真空油脂）比专门散热化合物，后者通常含有可在流到顶表面低粘度成分样品并污染它的EuTFC涂层。 </li><li>按样品向下使用镊子以同时施加力，两个对角相对的角的润滑脂的顶部，然后在适当位置夹住至少两个角部，使用黄铜螺钉和铍铜夹具。 注:如果在样品未牢固保持在适当位置，那么当电力被施加到它，使所得到的图像难于分析它可能漂移显著相对于所述显微镜。 </li><li>进行任何必要的电连接，例如用于电流和从样品到低温恒温器布线电压引线，注意不要让污染（ 例如焊剂的液滴）降落在EuTFC电影。 注:通过使用将做的工作，最好避免使用助焊剂这一步，在所有通量只有最小量做到这一点。如果Au线被用于连接到样品通量不应该是必要的。 </li><li>安装在它的xyz平移台上的样品的低温恒温器的显微镜下，安装其热屏蔽和光学窗口，并用涡轮分子泵抽空其样品的空间。 </li><li>覆盖低温恒温器的光学窗口用一块铝箔（或类似）的，以防止EuTFC的漂白通过在室内环境照明。小心不要损坏或执行此操作时污染显微镜镜头。 </li><li>冷却低温恒温器感兴趣的浴温度。对于本文描述的样品中，这通常是5 K和100之间K. 注意:不要让样品台坐125 K和175 K的温度长时间，因为在此范围内EuTFC影片最终会在结晶与不均​​匀发光特性也可随时间漂移一个多粒状的状态。通过该温度范围内冷却以2 K /分钟或更快的将确保不会出现此问题。如果低温恒温器在该温度范围意外地留时间太长，则EuTFC膜可以是可重复地通过简单地加热低温恒温器，以至少190 K中5分钟的复位"。 </li></ol> 5.收集热图像数据的<ol><li>安装在照明光学部件路径500纳米的截止波长的短通滤波器。 </li><li>安装用通带的中心波长= 610纳米，且FWHM = 10nm的带通滤波器，在收集光学器件的路径。 注意:通带窄是有利这里，因为它最小化的这有助于噪声，但不与信号背景光集合。该过滤器还必须选择以最小化它们之间的光谱串扰。 </li><li>允许光源升温，在我稳定TS稳态工作温度，并让相机冷却到它的平衡的工作温度。这大概需要30分钟两种情况。 </li><li>与所有的滤光器代替（由于聚焦位置是依赖于波长的）照射样本并对齐和显微镜聚焦到感兴趣区域。 注意:当不被成像的样品，使用或类似的快门，以避免EuTFC膜的样品和所得漂白的不必要的照明。 </li><li>收集的参考图像与施加到样品零电流。当收集的每个图像中，为暗计数，这可以从像素强烈变化到像素，以及给予一个显著偏移来自发光信号中的正确图像计数的校正。 注意:使用将取决于实验的要求的曝光条件（见讨论），但选择曝光条件，使得图像不包含饱和像素是很重要的。该需要参考图像由于所收集的发光强度通常会有所不同强烈依赖于样品的表面反射率，即使在其温度是完全均匀的。 </li><li>应用电偏压施加到样品中，相同的曝光条件作为基准下收集的图像，并且计算这些强度比。注:电偏压所需要的电平，其上正在研究的装置和自热行为的组合强烈依赖。这里提出的实施例典型地从几十mA，导致跨器件的偏压的几伏的数量级的样本偏置电流导致。 注:如果在样品显著相对于参考图像移动，则该像素数据应当被移动以进行补偿。 （然而，取决于相机的性能，这种转变可能在其对光的敏感度，这就是为什么该样品的运动应该如果在所有POS被最小化引入从像素到像素变化的噪声锡布尔赫丁）。如果需要在温度测量高的绝对精度，在灯强度的小的漂移可以被用于通过归一化图像到参考比校正为1中的样品（ 即 ，一个适合的区域，该区域足够远从自加热装置为能够不受其影响）。 </li><li>重复步骤5.6对所有感兴趣的偏置条件，同时保持浴温度恒定。 </li><li>所有感兴趣的浴温度重复步骤5.4至5.7。 注:根据低温恒温器，样品可能需要重新调整，并在每一个新浴温度重新聚焦。 </li></ol> 6.校准结果的<ol><li>收集零施加电流足以覆盖所关注的整个温度范围内的参考图像。 3〜4的图像在各温度下将足以建立的再现性，而为20K间距会给足够的数据点，以产生一个准确的校准曲线。 （参见图1b &lt;/强&gt;）。 </li><li>从该曲线，转换归一化强度图像转换成温度图。虽然绝对发光强度样品的局部表面反射率在很大程度上取决于其相对于温度的标准化行为只有通过这种非常弱的影响。 </li></ol> 7.样品储存和电影再利用<ol><li>与往常一样，继续由环境光保护漂白电影。注意:如果需要，在样品的EuTFC涂层能够承受重复的热循环，并保持在高真空时，其特性将保持稳定历时2-3周。 注:然而，储存在室温下高真空，即使，影片将降低超过2-3个月。 （变色和该膜的粗糙化可以在光学显微镜下容易看到）。如果这发生在这需要额外的热图像的样品，然后清洁该膜并更换它按照步骤1〜3。 </li></ol>

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The authors have nothing to disclose.

这表现在我们的研究结果，在本文中描述的技术产生的微器件的高分辨率热图像，具有良好的灵敏度，并且仅使用简单的光学显微镜设备。这相对于替代方法的技术（下面将要讨论的）的优点是最强的在大约250 K和下面，这意味着它的最重要的应用可用于研究，其被设计成在低温浴温度下操作的设备的自加热。这些包括超导电流磁带（其中骤冷成核是关键工程感兴趣的），用于光学检测窄带隙半导体，和新颖的高T C的电子设备，其电阻值随T.滴如果该技术以最佳灵敏度来工作，那么关键是要遵循正确的程序的膜的沉积。样品表面必须彻底清洗（步骤协议S×1.1至1.5），则EuTFC粉末必须仔细研磨以去除可在膜（步骤2.4）的均匀性产生不利影响的任何团块，并且膜升华必须为了保存的正确螯合以正确的速率发生铕离子（步骤3.3和3.4）。在低温下的膜的再结晶可提高实验噪声水平，但也可以根据在步骤4.7描述的相反这个问题。应使用的照明和曝光参数，并将得到的信号与噪声，取决于实验的要求。在这里，我们讨论一些这限制了该技术的性能的考虑。 有噪声四个主要的贡献可能在该实验中，即光子散粒噪声，在膜中，在照相机像素灵敏度变化，以及照相机暗计数的散粒噪声的发光响应微观变化。其中I是激发了照度（我每像素相当于样品面积的单元），F（T）是用于该膜的（每个像素的等效面积，其由局部膜厚度的影响）的T依赖性整体发光转换效率ncident光子，S是CCD计数从每入射光子的像素产率（在612 =纳米），和D是收集曝光时间t暗计数的数目，则当用P像素平均，这些参数将被近似正态分布如下: <img alt="方程" src="/files/ftp_upload/53948/53948eq1.jpg" /> σF（T）取决于EuTFC涂层的均匀性，而在像素到像素的光灵敏度和暗计数率的标准偏差σD中的标准偏差强度σs取决于相机的性能。收集用P像素时间t的计数因此有平均: <img alt="方程" src="/files/ftp_upload/53948/53948eq2.jpg" />其中最后一项对应于暗计数的贡献，和方差: <img alt="方程" src="/files/ftp_upload/53948/53948eq3.jpg" />因此，在当用P像素与总曝光时间t的平均测得的温度的标准误差由下式给出: <img alt="方程" src="/files/ftp_upload/53948/53948eq4.jpg" />对于一种高度均匀的膜和具有低像素响应非均匀性的CCD，在σF中的术语（T）和强度σs分别通常可以忽略不计。因此，该温度误差简化为: <img alt="方程" src="/files/ftp_upload/53948/53948eq5.jpg" />对于条件normall在该技术中采用的Y，发光光子收集的速率是每像素每秒5000点的光子的数量级。对于现代冷却CCD照相机，暗计数的速率，因此σD是比这少显著，这意味着σT被通常由光子散粒噪声19的限制。如果σD可以被忽略不计，然后将温度误差进一步简化为: <img alt="方程" src="/files/ftp_upload/53948/53948eq6.jpg" />提高照明强度从而降低对于任何给定σŤ所需的曝光时间，特别是在特殊情况下，其中所述发光收率是低的（ 例如，在温度接近300°K），并且其中暗计数实际上显著。然而，强烈UV照明可以photodope流子注入半导体样品，并打破超导那些库珀对，第ereby扰动设备的属性正在研究中。在样品其表面必须冷浴弱的热路径，强照明也可能引入导致在样品温度的上升显著的热负荷。 所有这些考虑的可能有时必要低照明强度和更长的暴露时间。作为变形例，更短的曝光可能需要图像快速的现象，如灯丝电流振荡或呼吸模式 20，或急冷发展的超导体的毫秒时间尺度。当需要高的绝对温度测量的信号噪声比，然后更长的总的曝光时间被称为对。这可能需要多次曝光的总和，这取决于CCD电子的位分辨率。图像强化相机已经接近单光子探测效率，并提供图像噪声之间的一个更具吸引力的权衡，生病umination强度，平均面积，和曝光速度，尽管在较高的系统成本。 总之，我们在这里描述的热致成像技术提供样品表面温度的直接定量测量，具有高的时间和空间分辨率。它也是在很宽的温度范围内有效，从5 K至300 K.正如引言中所描述的，替代的技术存在，但这些优惠的优点和缺点的组合。 扫描探针技术提供出色的灵敏度，在长的测量时间和高度专业化的设备的成本。甲最近出版的热电磁光技术也提供了极好的灵敏度21。然而，该技术依赖于放置在样品，这限制了空间分辨率的顶部上的亚铁磁性石榴石晶体指示器，特别是其中所述样品是不平坦的地形。在上述温度300 K，从EuTFC发光收率变低，并且从样品红外线黑体辐射的直接成像成为更有效的技术。

许多电子装置经历强烈的自我加热时电偏置到它们的正常操作条件。这通常是由于低导热性（例如，在半导体）和高功率消耗密度的组合。此外，在具有半导电状电阻器件（ 即具有∂ρ/∂Ť&lt;0）人们早已知道，存在局部的热失控的在一定的偏置条件1,2的可能性，其中，所述偏置电流流过不是均匀地通过该装置，而是在其与高度局部化的自加热有关，通常在微米的尺度窄的细丝。 了解这种自热物理学可能在某些情况下是必不可少的用于优化特定装置的设计，这意味着用于成像技术的温度上微米尺度是很有用。已经有最近的从技术发展的两个领域中这种技术的兴趣死灰复燃。其中第一项是用于在高温超导带成像淬火工艺，其中热显微成像允许淬火成核位点进行识别和研究3,4。所述第二应用程序是用于在叠层固有的约瑟夫逊结太赫兹光源，这是从的Bi 2的Sr 2 CaCu 2 O 8制成理解自加热。这些具有低的热导率和沿着电流流动的方向相关的半导体状的导电性（ 即，它们的晶体C轴）的组合，如上所述。它们不仅显示出实验复杂不均匀的自加热行为5，6，7，8 </sup&gt;，9，10，11就已经理论上预言，这可能是太赫兹功率发射12，13是有益的。 许多技术存在用于在微观长度尺度的样品的温度成像。最初采用这里所描述的热致技术用于半导体器件接近室温14，15，16但最近在低温浴温度下大于3，4，10，11中所述的超导条带和太赫兹源得到了应用。在CCD相机的分辨率和信号与噪声的性能提升已经使相当大的性能改进这一技术在过去的几十年。欧盟配位络合物铕thenoyltrifluoroacetonate（EuTFC）具有旋光发光是强烈依赖于温度的。在这个复杂的有机配体有效地吸收在宽带围绕345nm处的UV光。该能量通过分子内激发转移辐射较少的铕离子，其通过发光光子的在612纳米发射的复杂返回到其基态。强温度依赖性源于能量转移过程 17为使涂有该材料的物体的敏感的热探针。当涂层是激发近紫外源 - 诸如汞短弧灯 - 具有较低发光强度的区域对应于更高的局部温度。将得到的图像通过光学显微镜的分辨率和LUM的波长在空间分辨率限制inescence（在实践中，围绕1微米）。取决于所要求的信噪比，时间分辨率仅由照相机的快门速度由发光（不超过500微秒）15的衰减时间限制，并且更根本。这些特性使该技术器件温度的非常快的探测器，其产生直接的温度测量，使用相对简单和经济的设备。 这种技术被其它基团发表在过去的变化已采用小的浓度溶解在聚合物膜和旋涂到该样品表面3,4铕螯合物。这导致了涂层，该涂层是高度均匀的局部，但其具有在样品形貌的步骤显著厚度变化 - 如通常发生在微型 - 导致在发光响应WH强的空间变化ICH可以给图像伪影。我们在此描述的技术的变化采用热升华在真空中。这不仅避免了宏观膜厚度变化的问题，但每单位面积实现的更高浓度EuTFC提高显著的灵敏度并且降低了图像采集时间。一个相关技术采用SiC的涂层颗粒的表面，而不是EuTFC 7，8，9上。碳化硅提供温度灵敏度可比这里描述的EuTFC涂料，但该颗粒的尺寸限制了产生的图像的平滑度和分辨率。 几个其它技术存在，这提供的优点和缺点的不同组合。从样品的黑体辐射的直接红外成像是简单并具有几微米的空间分辨率，但是当样品是显著是唯一有效的LY高于室温。扫描探针显微镜热技术（例如扫描显微镜热电偶或开尔文探针显微镜）提供极好的灵敏度和空间分辨率，但是具有缓慢图像采集时间，必然由尖端的扫描速度，以及需要高度复杂的设备的限制。扫描激光或电子束扫描热显微镜措施时，一个调制光束跨过的电流偏置装置6，7，18的表面光栅化的电压扰动。这提供了优异的灵敏度，并且是比扫描探针技术稍快，但再次需要高度复杂的设备，并且还给出了样品的温度的间接，定性地图。

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Europium thenoyltrifluoroacetonate powder</td>
			<td>Sigma-Aldrich</td>
			<td>176494-1G</td>
			<td>Also known as Europium tris[3-(trifluoromethylhydroxymethylene)-(+)-camphorate]</td>
		</tr>
		<tr>
			<td>Mercury short-arc lamp with flexible light guide</td>
			<td>Lumen Dynamics</td>
			<td>X-Cite Exacte</td>
			<td>Light source includes internal iris and photosensor for output intensity feedback.</td>
		</tr>
		<tr>
			<td>Peltier-cooled CCD camera</td>
			<td>Princeton Instruments</td>
			<td>PIXIS 1024</td>
			<td>1024 x 1024 pixels, 16-bit resolution</td>
		</tr>
		<tr>
			<td>610 nm band-pass filter</td>
			<td>Edmund Optics</td>
			<td>65-164</td>
			<td>Passband has CWL 610 nm, FWHM 10 nm</td>
		</tr>
		<tr>
			<td>500 nm short-pass filter</td>
			<td>Edmund Optics</td>
			<td>84-706</td>
			<td>OD4 in stopband</td>
		</tr>
		<tr>
			<td>Helium flow cryostat with optical window</td>
			<td>Oxford Instruments</td>
			<td>MicrostatHe2</td>
			<td></td>
		</tr>
		<tr>
			<td>high vacuum grease</td>
			<td>Dow Corning</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Digital Current source</td>
			<td>Keithley</td>
			<td>Model 2400</td>
			<td>Computer-controllable current &#38; voltage source</td>
		</tr>
		<tr>
			<td>Digital Voltmeter</td>
			<td>Hewlett-Packard&#160;</td>
			<td>Model 34420A</td>
			<td>Digital Nanovoltmeter now available as Agilent Model 34420A</td>
		</tr>
	</tbody>
</table>

high-resolution thermal micro-imaging using europium chelate luminescent coatings

当偏置到它们的典型的操作条件微型电子设备通常经历显著自加热。本文介绍了一种方便的光学显微成像技术，其可被用于映射和量化这种行为。铕thenoyltrifluoroacetonate（EuTFC）具有612纳米的发光线，其活化效率随着温度的升高强烈下降，由于T中的Eu 3+离子和有机螯合化合物之间依赖性相互作用。这种材料可以通过在真空中升华热可以容易地涂布到样品表面。当涂层被激发紫外线（337纳米）的纳米612发光响应的光学显微图像可直接被转换成地图上的样品表面温度。这种技术提供（约1微米）的仅由光学显微镜有限的空间分辨率和时间分辨率由所采用的照相机的速度的限制。它提供的只是额外的好处需要相对简单的和非专用设备，并给样品温度的定量探测器。

用于进行该实验在低温浴温度下典型的测量配置的示例被示出在图1a中 ，而612纳米的发光响应强度与温度的典型曲线图1b绘制。 图2示出了的Bi 2的Sr 2 CaCu 2 O 8的THz源，其由堆叠的"固有"约瑟夫逊结的"台面"的尺寸为300×60×0.83微米的自加热的典型的热图像的一个例子，制造在单晶的表面上，并且具有86 K的超导T C 在这样的装置中，电流流动是沿c轴方向上（ 即，进入作为在图像中示出的页面的平面中），由于这种材料的极各向异性的电阻率。至于的Bi 2的Sr 2 CaCu 如图2a所示，ρC（T）2 O 8随着温度的升高，从而允许在一定的偏置条件热不稳定性和局部热失控的可能性强烈下降。该装置的热图像示于图2d，将其在文本下160X放大倍数1024×1024像素的CCD照相机上具有16位的分辨率所描述的，使用的4×2秒求和曝光收集，珀耳帖冷却至- 50℃。将样品与使用500nm的短通滤光器的短弧汞灯，和大约1瓦/ 平方厘米净强度照亮。为了避免如在第5.6节描述的由一个未自加热区归一化的图像的要求，灯是使用可变光阑与闭环反馈，以保持照明强度随时间变化操作。 c轴方向上产生的电流流自持灯丝通过该装置。在这种灯丝，电流密度比在台面的其余部分更高的5倍以上。对于台面在T 浴中的电流-电压特性= 25 K被示于图2b。这包含与所述热点的核/湮没在约我 偏压 =11毫安相关滞后的跳跃，并与从台面的电极端40和60 mA的相对端热点的跳跃。 图2c示出不同偏压条件下在台面表面温度的纵向横截面。对于这里所使用的照相机和成像条件，温度是噪声约0.2 K，当在直径为4微米的平滑化，对应于5×5像素区域在此magnifi阳离子。在台面和所述电极的边缘在图2d中可见的线是由于反射离开接近垂直的侧壁表面的工件。 图3示出在协议中描述的，应避免的情况下的原始图像的例子。 图3a示出了其中将膜使用EuTFC其中毫米大小的块状物存在升华一个612纳米的发光图像。 （参见步骤2.4）。这些升华的剧烈加热时，就到了样品沉积在直径EuTFC几微米的颗粒。 图3b显示了一个示例，其EuTFC涂层在150ķ结晶成域16小时后，导致不均匀和噪声的响应发光。 （参见步骤4.6）。 <img alt="图1" src="/files/ftp_upload/53948/53948fig1.jpg" /> 图1:热成像设置和典型CAL振器曲线。 （a）结构的显微镜，UV光源，以及低温恒温器具有光学窗口中，从参考文献10改性（b）中的响应曲线归一化到10 K中200nm的升华EuTFC膜。 <img alt="图2" src="/files/ftp_upload/53948/53948fig2.jpg" /> 图2:的Bi 2的Sr 2 CaCu 2 O 8台面的THz源:IV特性及热图像。对温度器件电阻（a）的（主）剧情。绘制低于T C蓝色方块是从在插图中所示的IV曲线外推值。 （b）第IV特性表示设备在T 浴约瑟夫逊结的滞后切换= 25 K，用于电流偏置台面。插图（ⅰ）和（ii）示出了跳转分别与热点的成核和重定位相关联的台面电阻。 （c）中台面的纵向温度的横截面。 （d）中在T 浴 = 25 K，从参照图11改性热图像，与左侧所示的台面传统的光学显微照片。 <a href="https://ecsource-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/53948/53948fig2large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图3" src="/files/ftp_upload/53948/53948fig3.jpg" /> 图3:实施例的问题，以避免与EuTFC膜。 （A）的薄膜升华不脱离EuTFC粉末去除大团块结晶，导致沉积在样品块。 （b）中膜（沉积在不同的台面），其已经在150ķ经历本地结晶在低温恒温器在16小时后，呈现出不均匀的发光响应。 <a href="https://ecsource-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/53948/53948fig3large.jpg" target="_blank">请点击此处</a>查看该图的放大版本。

Watch this Scientific Journal Video about High-resolution Thermal Micro-imaging Using Europium Chelate Luminescent Coatings at JoVE.com

High-resolution Thermal Micro-imaging Using Europium Chelate Luminescent Coatings

铕thenoyltrifluoroacetonate（EuTFC）具有在612纳米，其激活效率随温度强烈降低的光致发光线。如果涂有这种材料的薄膜的样品是微成像时，612纳米的发光响应强度可以被转换成样品表面温度的直接映射。

高分辨率热显微成像采用铕螯合物的荧光涂料

Micro-electronic devices often undergo significant self-heating when biased to their typical operating conditions. This paper describes a convenient ...

high-resolution-thermal-micro-imaging-using-europium-chelate

Nanyang Technological University

Research

JoVE Journal

Engineering

7.7K 次观看.  Argonne National Laboratory. 铕thenoyltrifluoroacetonate（EuTFC）具有在612纳米，其激活效率随温度强烈降低的光致发光线。如果涂有这种材料的薄膜的样品是微成像时，612纳米的发光响应强度可以被转换成样品表面温度的直接映射。 

视频: High-resolution Thermal Micro-imaging Using Europium Chelate Luminescent Coatings

High-resolution, High-speed, Three-dimensional Video Imaging with Digital Fringe Projection Techniques

Digital fringe projection (DFP) techniques provide dense 3D measurements of dynamically changing surfaces.&#160;Like the human eyes and brain, DFP uses triangulation between matching points in two views of the same scene at different angles to compute depth.&#160;However, unlike a stereo-based method, DFP uses a digital video projector to replace one of the cameras1. The projector rapidly projects a known sinusoidal pattern onto the subject, and the surface of the subject distorts these patterns in the camera&#8217;s field of view. Three distorted patterns (fringe images) from the camera can be used to compute the depth using triangulation.
Unlike other 3D measurement methods, DFP techniques lead to systems that tend to be faster, lower in equipment cost, more flexible, and easier to develop.&#160;DFP systems can also achieve the same measurement resolution as the camera.&#160;For this reason, DFP and other digital structured light techniques have recently been the focus of intense research (as summarized in1-5). Taking advantage of DFP, the graphics processing unit, and optimized algorithms, we have developed a system capable of 30&#160;Hz 3D video data acquisition, reconstruction, and display for over 300,000 measurement points per frame6,7.&#160;Binary defocusing DFP methods can achieve even greater speeds8.
Diverse applications can benefit from DFP techniques. Our collaborators have used our systems for facial function analysis9, facial animation10, cardiac mechanics studies11, and fluid surface measurements, but many other potential applications exist.&#160;This video will teach the fundamentals of DFP techniques and illustrate the design and operation of a binary defocusing DFP system.

This video describes the fundamentals of digital fringe projection techniques, which provide dense 3D measurements of dynamically changing surfaces.&#160;It also demonstrates the design and operation of a high-speed binary defocusing system based on these techniques.

Digital fringe projection (DFP) techniques provide dense 3D measurements of dynamically changing surfaces.&#160;Like the human eyes and brain, DFP uses ...

科研

工程学

Construction of a High Resolution Microscope with Conventional and Holographic Optical Trapping Capabilities

High resolution microscope systems with optical traps allow for precise manipulation of various refractive objects, such as dielectric beads 1 or cellular organelles 2,3, as well as for high spatial and temporal resolution readout of their position relative to the center of the trap. The system described herein has one such "traditional" trap operating at 980 nm. It additionally provides a second optical trapping system that uses a commercially available holographic package to simultaneously create and manipulate complex trapping patterns in the field of view of the microscope 4,5 at a wavelength of 1,064 nm. The combination of the two systems allows for the manipulation of multiple refractive objects at the same time while simultaneously conducting high speed and high resolution measurements of motion and force production at nanometer and piconewton scale.

The system described herein employs a traditional optical trap as well as an independent holographic optical trapping line, capable of creating and manipulating multiple traps. This allows for the creation of complex geometric arrangements of refractive particles while also permitting simultaneous high-speed, high-resolution measurements of the activity of biological enzymes.

高分辨率显微镜与常规和全息光学捕获能力建设

High resolution microscope systems with optical traps allow for precise manipulation of various refractive objects, such as dielectric beads 1 or cellular ...

Characterization of Thermal Transport in One-dimensional Solid Materials

The TET (transient electro-thermal) technique is an effective approach developed to measure the thermal diffusivity of solid materials, including conductive, semi-conductive or nonconductive one-dimensional structures. This technique broadens the measurement scope of materials (conductive and nonconductive) and improves the accuracy and stability. If the sample (especially biomaterials, such as human head hair, spider silk, and silkworm silk) is not conductive, it will be coated with a gold layer to make it electronically conductive. The effect of parasitic conduction and radiative losses on the thermal diffusivity can be subtracted during data processing. Then the real thermal conductivity can be calculated with the given value of volume-based specific heat (&#961;cp), which can be obtained from calibration, noncontact photo-thermal technique or measuring the density and specific heat separately. In this work, human head hair samples are used to show how to set up the experiment, process the experimental data, and subtract the effect of parasitic conduction and radiative losses.

The TET (transient electro-thermal) technique is an effective approach developed to measure the thermal diffusivity of solid materials.

在一维固体材料的热传输的特性

The TET (transient electro-thermal) technique is an effective approach developed to measure the thermal diffusivity of solid materials, including ...

The Preparation of Electrohydrodynamic Bridges from Polar Dielectric Liquids

Horizontal and vertical liquid bridges are simple and powerful tools for exploring the interaction of high intensity electric fields (8-20 kV/cm) and polar dielectric liquids. These bridges are unique from capillary bridges in that they exhibit extensibility beyond a few millimeters, have complex bi-directional mass transfer patterns, and emit non-Planck infrared radiation. A number of common solvents can form such bridges as well as low conductivity solutions and colloidal suspensions. The macroscopic behavior is governed by electrohydrodynamics and provides a means of studying fluid flow phenomena without the presence of rigid walls. Prior to the onset of a liquid bridge several important phenomena can be observed including advancing meniscus height (electrowetting), bulk fluid circulation (the Sumoto effect), and the ejection of charged droplets (electrospray). The interaction between surface, polarization, and displacement forces can be directly examined by varying applied voltage and bridge length. The electric field, assisted by gravity, stabilizes the liquid bridge against Rayleigh-Plateau instabilities. Construction of basic apparatus for both vertical and horizontal orientation along with operational examples, including thermographic images, for three liquids (e.g., water, DMSO, and glycerol) is presented.

Horizontal and vertical electrohydrodynamic liquid bridges are simple and powerful tools for exploring the interaction of high intensity electric fields and polar dielectric liquids. The construction of basic apparatus and operational examples, including thermographic images, for three liquids (e.g., water, DMSO, and glycerol) is presented.

高压直流电桥从极地介电液的制备

Horizontal and vertical liquid bridges are simple and powerful tools for exploring the interaction of high intensity electric fields (8-20 kV/cm) and ...

Thermal Measurement Techniques in Analytical Microfluidic Devices

Thermal measurement techniques have been used for many applications such as thermal characterization of materials and chemical reaction detection. Micromachining techniques allow reduction of the thermal mass of fabricated structures and introduce the possibility to perform high sensitivity thermal measurements in the micro-scale and nano-scale devices. Combining thermal measurement techniques with microfluidic devices allows performing different analytical measurements with low sample consumption and reduced measurement time by integrating the miniaturized system on a single chip. The procedures of thermal measurement techniques for particle detection, material characterization, and chemical detection are introduced in this paper.

Here, we present three protocols for thermal measurements in microfluidic devices.

在分析微流体装置的热测量技术

Thermal measurement techniques have been used for many applications such as thermal characterization of materials and chemical reaction detection. ...

Seedless Growth of Bismuth Nanowire Array via Vacuum Thermal Evaporation

Here a seedless and template-free technique is demonstrated to scalably grow bismuth nanowires, through thermal evaporation in high vacuum at RT. Conventionally reserved for the fabrication of metal thin films, thermal evaporation deposits bismuth into an array of vertical single crystalline nanowires over a flat thin film of vanadium held at RT, which is freshly deposited by magnetron sputtering or thermal evaporation. By controlling the temperature of the growth substrate the length and width of the nanowires can be tuned over a wide range. Responsible for this novel technique is a previously unknown nanowire growth mechanism that roots in the mild porosity of the vanadium thin film. Infiltrated into the vanadium pores, the bismuth domains (~ 1 nm) carry excessive surface energy that suppresses their melting point and continuously expels them out of the vanadium matrix to form nanowires. This discovery demonstrates the feasibility of scalable vapor phase synthesis of high purity nanomaterials without using any catalysts.

A protocol for seedless and high yield growth of bismuth nanowire arrays through vacuum thermal evaporation technique is presented.

铋纳米线阵列通过真空热蒸发无核增长

Here a seedless and template-free technique is demonstrated to scalably grow bismuth nanowires, through thermal evaporation in high vacuum at RT. ...

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy

High resolution optical spectroscopy methods are demanding in terms of either technology, equipment, complexity, time or a combination of these. Here we demonstrate an optical spectroscopy method that is capable of resolving spectral features beyond that of the spin fine structure and homogeneous linewidth of single quantum dots (QDs) using a standard, easy-to-use spectrometer setup. This method incorporates both laser and photoluminescence spectroscopy, combining the advantage of laser line-width limited resolution with multi-channel photoluminescence detection. Such a scheme allows for considerable improvement of resolution over that of a common single-stage spectrometer. The method uses phonons to assist in the measurement of the photoluminescence of a single quantum dot after resonant excitation of its ground state transition. The phonon&#39;s energy difference allows one to separate and filter out the laser light exciting the quantum dot. An advantageous feature of this method is its straight forward integration into standard spectroscopy setups, which are accessible to most researchers.

The manuscript describes a method of phonon-assisted quasi-resonant fluorescence spectroscopy that incorporates both laser-limited resolution and photoluminescence (PL) spectroscopy. This method utilizes optical phonons to provide linewidth-limited resolution spectra of atom-like semiconductor structures in the energy domain. The method is also easily realized with a single spectrometer optical spectroscopy setup.

高分辨率声子辅助准共振荧光光谱仪

High resolution optical spectroscopy methods are demanding in terms of either technology, equipment, complexity, time or a combination of these. Here we ...

Fiber Optic Distributed Sensors for High-resolution Temperature Field Mapping

The reliability of computational fluid dynamics (CFD) codes is checked by comparing simulations with experimental data. A typical data set consists chiefly of velocity and temperature readings, both ideally having high spatial and temporal resolution to facilitate rigorous code validation. While high resolution velocity data is readily obtained through optical measurement techniques such as particle image velocimetry, it has proven difficult to obtain temperature data with similar resolution. Traditional sensors such as thermocouples cannot fill this role, but the recent development of distributed sensing based on Rayleigh scattering and swept-wave interferometry offers resolution suitable for CFD code validation work. Thousands of temperature measurements can be generated along a single thin optical fiber at hundreds of Hertz. Sensors function over large temperature ranges and within opaque fluids where optical techniques are unsuitable. But this type of sensor is sensitive to strain and humidity as well as temperature and so accuracy is affected by handling, vibration, and shifts in relative humidity. Such behavior is quite unlike traditional sensors and so unconventional installation and operating procedures are necessary to ensure accurate measurements. This paper demonstrates implementation of a Rayleigh scattering-type distributed temperature sensor in a thermal mixing experiment involving two air jets at 25 and 45 &#176;C. We present criteria to guide selection of optical fiber for the sensor and describe installation setup for a jet mixing experiment. We illustrate sensor baselining, which links readings to an absolute temperature standard, and discuss practical issues such as errors due to flow-induced vibration. This material can aid those interested in temperature measurements having high data density and bandwidth for fluid dynamics experiments and similar applications. We highlight pitfalls specific to these sensors for consideration in experiment design and operation.

We demonstrate use of a fiber optic distributed sensor for mapping the temperature field of mixing air jets. The Rayleigh scattering-based sensor generates thousands of data points along a single fiber to provide exceptional spatial resolution that is unattainable with traditional sensors such as thermocouples.

对于高分辨率温度场测绘光纤分布式传感器

The reliability of computational fluid dynamics (CFD) codes is checked by comparing simulations with experimental data. A typical data set consists ...

The Evolution of Silica Nanoparticle-polyester Coatings on Surfaces Exposed to Sunlight

Corrosion of metallic surfaces is prevalent in the environment and is of great concern in many areas, including the military, transport, aviation, building and food industries, amongst others. Polyester and coatings containing both polyester and silica nanoparticles (SiO2NPs) have been widely used to protect steel substrata from corrosion. In this study, we utilized X-ray photoelectron spectroscopy, attenuated total reflection infrared micro-spectroscopy, water contact angle measurements, optical profiling and atomic force microscopy to provide an insight into how exposure to sunlight can cause changes in the micro- and nanoscale integrity of the coatings. No significant change in surface micro-topography was detected using optical profilometry, however, statistically significant nanoscale changes to the surface were detected using atomic force microscopy. Analysis of the X-ray photoelectron spectroscopy and attenuated total reflection infrared micro-spectroscopy data revealed that degradation of the ester groups had occurred through exposure to ultraviolet light to form COO&#903;, -H2C&#903;, -O&#903;, -CO&#903; radicals. During the degradation process, CO and CO2 were also produced.

Two types of surfaces, polyester-coated steel and polyester coated with a layer of silica nanoparticles, were studied. Both surfaces were exposed to sunlight, which was found to cause substantial changes in the chemistry and nanoscale topography of the surface.

表面上的纳米硅聚酯涂料暴露在阳光下的演变

Corrosion of metallic surfaces is prevalent in the environment and is of great concern in many areas, including the military, transport, aviation, ...

Method for Recording Broadband High Resolution Emission Spectra of Laboratory Lightning Arcs

Lightning is one of the most common and destructive forces in nature and has long been studied using spectroscopic techniques, first with traditional camera film methods and then digital camera technology, from which several important characteristics have been derived. However, such work has always been limited due to the inherently random and non-repeatable nature of natural lightning events in the field. Recent developments in lightning test facilities now allow the reproducible generation of lightning arcs within controlled laboratory environments, providing a test bed for the development of new sensors and diagnostic techniques to understand lightning mechanisms better. One such technique is a spectroscopic system using digital camera technology capable of identifying the chemical elements with which the lightning arc interacts, with these data then being used to derive further characteristics. In this paper, the spectroscopic system is used to obtain the emission spectrum from a 100 kA peak, 100 &#181;s duration lightning arc generated across a pair of hemispherical tungsten electrodes separated by a small air gap. To maintain a spectral resolution of less than 1 nm, several individual spectra were recorded across discrete wavelength ranges, averaged, stitched, and corrected to produce a final composite spectrum in the 450 nm (blue light) to 890 nm (near infrared light) range. Characteristic peaks within the data were then compared to an established publicly available database to identify the chemical element interactions. This method is readily applicable to a variety of other light emitting events, such as fast electrical discharges, partial discharges, and sparking in electrical equipment, apparatus, and systems.

Emission spectroscopy techniques have traditionally been used to analyze inherently random lightning arcs occurring in nature. In this paper, a method developed to obtain the emission spectroscopy from reproducible lightning arcs generated within a laboratory environment is described.

记录实验室闪电弧宽带高分辨率发射光谱的方法

Lightning is one of the most common and destructive forces in nature and has long been studied using spectroscopic techniques, first with traditional ...