de Jonge Niels, Allioux Myriam, Oostveen Jim T, Teo Kenneth B K, Milne William I
Philips Research, Professor Holstlaan 4, 5656 AA Eindhoven, The Netherlands.
Phys Rev Lett. 2005 May 13;94(18):186807. doi: 10.1103/PhysRevLett.94.186807. Epub 2005 May 11.
The figure of merit for the electron optical performance of carbon-nanotube (CNT) electron sources is presented. This figure is given by the relation between the reduced brightness and the energy spread in the region of stable emission. It is shown experimentally that a CNT electron source exhibits a highly stable emission process that follows the Fowler-Nordheim theory for field emission, fixing the relationship among the energy spread, the current, and the radius. The performance of the CNT emitter under realistic operating conditions is compared with state-of-the-art electron point sources. It is demonstrated that the reduced brightness is a function of the tunneling parameter, a measure of the energy spread at low temperatures, only, independent of the geometry of the emitter.
给出了碳纳米管（CNT）电子源电子光学性能的品质因数。该品质因数由稳定发射区域内的折合亮度与能量展宽之间的关系给出。实验表明，碳纳米管电子源呈现出高度稳定的发射过程，遵循场发射的福勒-诺德海姆理论，确定了能量展宽、电流和半径之间的关系。将碳纳米管发射器在实际工作条件下的性能与最先进的电子点源进行了比较。结果表明，折合亮度仅是隧穿参数的函数，隧穿参数是低温下能量展宽的一种度量，与发射器的几何形状无关。
