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翻譯社

"This 'unipolar' electroluminescence provides a novel diagnostic tool for the identification of defects翻譯社 trapped charges and dielectric environment changes that lead to the scattering of carriers," he said.

根據Avouris的說法，由於此些奈米管的一維特性，及從而產生的電子-電洞強烈交互感化，上述進程透過大塊材料中的雷同進程，被增強若干數目級翻譯

The nanotubes also emitted in ambipolar mode, when both electrons and holes were flowing. "Electrons and holes independently injected from the opposite ends of an ambipolar nanotube transistor recombine and emit light," explained Avouris. "This is the same mechanism as that operating in macroscopic light emitting diodes."
在雙極性模式中，當電子及電洞活動時，此些奈米管也發出紅外線光翻譯Avouris注釋說：「分別從雙極性奈米管電晶體反向端被導入的電子及電洞，從新連系並發出光。

The researchers reported their work in Nano Letters.
此些研究人員於《奈米記事》期刊中，記敘了他們的研究。


原文網址：http://nanotechweb.org/articles/news/5/6/13/1
翻譯：許東榮

美國IBM公司及荷蘭特文特大學的研究人員們已發現，來自碳奈米管晶格缺點，由電流激發的紅外線放射，可能供給闡發奈米管佈局的方式翻譯此現象僅當一種載體(電洞或電子)在碳奈米管中活動時産生。也就是，産生於碳奈米管以單極性而非雙極性運作時翻譯

According to Avouris翻譯社 the process is enhanced many orders of magnitude over corresponding processes in bulk materials because of the one-dimensional character of the nanotubes and of the resulting strong electron-hole interaction.

But there's one important difference: there are no dopants introduced in the ambipolar nanotube transistor. "This allows the translation of the light emission spot at will along the length of a long nanotube by simply changing the voltage applied to the gate of the transistor翻譯社" said Avouris.
不過，有項重要差異：在雙極性奈米管電晶體中，沒有攙雜被引入翻譯Avouris傳播鼓吹：「這使得光發射點能藉由純真改變，施加於此種電晶體閘極的電壓，而沿著長奈米管的長度隨意轉移。」

Researchers at IBM, US, and the University of Twente in The Netherlands have found that current-induced infrared emission from defects in carbon nanotubes could provide a way of analysing the nanotubes' structure. The phenomenon takes place when only one type of carrier (holes or electrons) is flowing in the nanotube, i.e. when it is in unipolar rather than ambipolar operation.

"The observed electroluminescence is localized at specific spots along the nanotube and it is intense翻譯社" Phaedon Avouris of IBM told nanotechweb.org. "We found that this new emission is the result of local acceleration of carriers due to voltage drops at nanotube or substrate defects. The accelerated ('hot') carriers then excite electron-hole pairs whose recombination produces the light."
IBM公司的Phaedon Avouris告知nanotechweb.org.：「該被察看到的電致發光，集中於沿著該奈米管的諸多特定地方且強烈。他們發現，上述新放射是由於，在奈米管或基片中的晶格缺點地方，電壓降落造成載體局部加快的了局翻譯在那情況下，這些加速的('熱')載體激發了，重組產生光的電子-電洞對。

Now the scientists are working to enhance the electroluminescence yield of carbon nanotubes翻譯社 as well as evaluating other one-dimensional nanostructures.
除評估其他一維奈米構造物以外，今朝此些科學家正致力於增強碳奈米管的電致發光場翻譯

Avouris and colleagues made carbon nanotube field-effect transistors on oxidized silicon wafers. The substrate was heavily doped and acted as the gate for the device. The source and drain electrodes翻譯社 meanwhile翻譯社 consisted of 20 nm of palladium on a 0.5 nm adhesion layer of titanium. The team coated some devices with a poly(methyl methacrylate) (PMMA) layer to look at the effects of a change in local dielectric environment on the electroluminescence.
Avouris及同寅們在氧化的矽晶片上，製作了諸多碳奈米管場效電晶體翻譯該基片被大量攙雜，是以充任了上述裝配的閘極翻譯另外一方面，源極與汲極這兩電極是由20奈米的鈀，在0.5奈米的鈦接合層上構成。

此些可能包羅，奈米及份子電子手藝中的光交聯、暗碼術或個別份子光譜手藝翻譯

The researchers say they hope to couple the excellent electrical and optical properties of nanotubes to develop electrically-excited nano-light emission sources and light detection devices. "We are aiming at applications that require nano-sized light sources翻譯社" said Avouris. "These may include optical interconnects in nano- and molecular electronics, cryptography, or individual molecule spectroscopy."
此些研究人員透露表現，他們期盼能連系奈米管最佳的電氣及光學屬性，來開辟由電力激起的奈米發光源及光檢測裝配翻譯Avouris傳播鼓吹：「他們正以諸多需要奈米級光源的利用為方針。

Avouris傳播鼓吹：「該'單極性'電致發光提供了，確認晶格缺點、被陷捕電荷及致使載體散射之電介質環境改變等的新檢測對象。」