scanning-probe-single-electron-capacitance-spectroscopy

Scanning-probe Single-electron Capacitance Spectroscopy

The integration of low-temperature scanning-probe techniques and single-electron capacitance spectroscopy represents a powerful tool to study the ...

Michigan State University

Saint Louis University

We present a numerical method to model electric-field-sensitive scanning probe microscopy measurements which allows for a tip of arbitrary shape and invokes image charges to exactly account for a sample dielectric overlayer. The method is applied to calculate the spatial resolution of a subsurface charge accumulation imaging system, achieving reasonable agreement with experiment.

Modeling electric-field-sensitive scanning probe measurements for a tip of arbitrary shape.

Nous pr&eacute;sentons une m&eacute;thode num&eacute;rique pour mesures microscopie sonde analyse de mod&egrave;le sensible-champ &eacute;lectrique qui permet un pourboire de forme arbitraire et sollicite les accusations d&#39;image exactement compte pour une sur-couche di&eacute;lectrique de l&#39;&eacute;chantillon. La m&eacute;thode est appliqu&eacute;e pour calculer la r&eacute;solution spatiale d&#39;une accumulation de charge sous la surface, syst&egrave;me d&#39;imagerie, de parvenir &agrave; un accord raisonnable avec les donn&eacute;es exp&eacute;rimentales.

Mod&eacute;lisation analyse mesures sonde sensible-champ &eacute;lectrique pour une pointe de forme arbitraire.

Vi presentiamo un metodo numerico per le misurazioni microscopia di modello elettrico-campo-sensibile scansione sonda che permette una punta di forma arbitraria e richiama cariche immagine per proprio conto per un overlayer dielettrico campione. Il metodo &egrave; applicato per calcolare la risoluzione spaziale di un accumulo di carica sottosuolo imaging system, raggiungendo un accordo ragionevole con esperimento.

Modellazione elettrica-campo-sensibile scansione sonda misurazioni per una punta di forma arbitraria.

Controllable patterning and CVD growth of isolated carbon nanotubes with direct parallel writing of catalyst using dip-pen nanolithography.

Structuration contr&ocirc;lable et croissance de CVD des nanotubes de carbone isol&eacute;s avec une &eacute;criture parall&egrave;le directe de catalyseur &agrave; l&#39;aide de dip-pen nanolithography.

Patterning controllabile e crescita CVD di nanotubi di carbonio isolato con scrittura diretta parallela del catalizzatore utilizzando la nanolitografia dip-pen.

Semiconductor GaN NWs are promising components in next generation nano- and optoelectronic systems. In addition to their direct band gap, they exhibit piezoelectricity, which renders them particularly attractive in energy harvesting applications for self-powered devices. Nanowires are often considered as one-dimensional nanostructures; however, the electromechanical coupling leads to a third rank tensor that for wurtzite crystals (GaN NWs) possesses three independent coefficients, d(33), d(13), and d(15). Therefore, the full piezoelectric characterization of individual GaN NWs requires application of electric fields in different directions and measurements of associated displacements on the order of several picometers. In this Letter, we present an experimental approach based on scanning probe microscopy to directly quantify the three-dimensional piezoelectric response of individual GaN NWs. Experimental results reveal that GaN NWs exhibit strong piezoelectricity in three dimensions, with up to six times the effect in bulk. Based on finite element modeling, this finding has major implication on the design of energy harvesting systems exhibiting unprecedented levels of power density production. The presented method is applicable to other piezoelectric NW materials as well as wires manufactured along different crystallographic orientations.

Individual GaN nanowires exhibit strong piezoelectricity in 3D.

Semi-conducteurs GaN NWs sont des &eacute;l&eacute;ments prometteurs dans la prochaine g&eacute;n&eacute;ration de syst&egrave;mes nano - et opto&eacute;lectroniques. En plus de leur direct bande interdite, ils pr&eacute;sentent pi&eacute;zo&eacute;lectricit&eacute;, ce qui les rend particuli&egrave;rement attractif dans les applications de r&eacute;colte &eacute;nerg&eacute;tique pour les appareils auto-aliment&eacute;s. Nanofils sont souvent consid&eacute;r&eacute;s comme des nanostructures unidimensionnels ; Cependant, les sondes de couplage &eacute;lectrom&eacute;canique &agrave; un troisi&egrave;me rang tenseur qui pour cristaux wurtzite (GaN NWs) poss&egrave;de trois coefficients ind&eacute;pendants, d(33), d(13) et d(15). La caract&eacute;risation compl&egrave;te pi&eacute;zo&eacute;lectrique d&#39;individuels GaN NWs n&eacute;cessite donc, application de champs &eacute;lectriques dans des directions diff&eacute;rentes et les mesures de d&eacute;placements associ&eacute;s sur l&#39;ordre de plusieurs picom&egrave;tres. Dans cette lettre, nous pr&eacute;sentons une approche exp&eacute;rimentale bas&eacute;e sur la microscopie de sonde pour mesurer directement la r&eacute;ponse pi&eacute;zo&eacute;lectrique en trois dimensions d&#39;individu Qu&#39;exp&eacute;rimental GaN NWs. r&eacute;sultats r&eacute;v&egrave;lent que GaN NWs pi&egrave;ce forte pi&eacute;zo&eacute;lectricit&eacute; en trois dimensions, avec jusqu&#39;&agrave; six fois l&#39;effet en vrac. Bas&eacute; sur la mod&eacute;lisation par &eacute;l&eacute;ments finis, cette constatation a implication majeure sur le design des syst&egrave;mes pr&eacute;sentant des niveaux sans pr&eacute;c&eacute;dent de la production de densit&eacute; de puissance. La m&eacute;thode pr&eacute;sent&eacute;e est applicable aux autres mat&eacute;riaux NW pi&eacute;zo&eacute;lectrique ainsi que des fils fabriqu&eacute;s suivant diff&eacute;rentes orientations cristallographiques.

Individuels GaN nanofils pi&egrave;ce forte pi&eacute;zo&eacute;lectricit&eacute; en 3D.

Semiconduttori GaN NWs sono componenti promettenti nella prossime generazione di sistemi nano - e optoelettronici. Oltre a loro diretto band gap, esibiscono la piezoelettricit&agrave;, che li rende particolarmente attraenti in applicazioni di energia raccolta per dispositivi autoalimentati. Nanofili sono spesso considerati come nanostrutture unidimensionale; Tuttavia, l&#39;accoppiamento elettromeccanico conduce un terzo Rank tensore che per cristalli wurtzite (GaN NWs) possiede tre coefficienti indipendenti, d(33), d(13) e d(15). Pertanto, la caratterizzazione completa piezoelettrica di singoli GaN NWs richiede applicazione di campi elettrici in direzioni diverse e le misure degli spostamenti associati dell&#39;ordine di alcuni picometri. In questa lettera, vi presentiamo un approccio sperimentale basato sulla microscopia sonda per quantificare direttamente la risposta piezoelettrica tridimensionale dell&#39;individuo che Gan NWs. sperimentale risultati rivelano che GaN NWs presentano forti piezoelettricit&agrave; in tre dimensioni, con fino a sei volte l&#39;effetto alla rinfusa. Basato sulla modellazione agli elementi finiti, questa scoperta ha importanti implicazioni sulla progettazione di energia raccolta sistemi esibendo senza precedenti livelli di produzione di densit&agrave; di potenza. Il metodo proposto &egrave; applicabile ad altri piezoelettrico NW materiali cos&igrave; come fili fabbricati lungo diversi orientamenti cristallografici.

Irma Kuljanishvili

Department of Physics and Astronomy

Michigan State University

Scanning-probe Single-electron Capacitance Spectroscopy

Irma Kuljanishvili

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Department of Physics and Astronomy

Michigan State University

Scanning-probe Single-electron Capacitance Spectroscopy

Department of Physics and Astronomy