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arXiv · 1409.2644

Dynamic Control of Local Field Emission Current from Carbon Nanowalls

Ying Wang·Yumeng Yang·Yihong Wu
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Abstract

We report on a systematic study of modulation of the field emission current from carbon nanowalls using a sharp probe as the anode in an ultrahigh vacuum system. Modulation of the local emission current was achieved by either varying the anode-cathode distance (d) with the aid of an AC magnetic field or superimposing a small AC bias on a DC bias during the field emission measurement. Current modulation ratio of over two orders of magnitude was achieved with the modulation becoming more efficient at a smaller d. The experimental results are discussed using the Fowler-Nordheim theory in combination with a simple cantilever model to account for the modulation effect. The experimental results demonstrated good static stability and dynamic controllability of local field emission current from the carbon nanowalls.

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Ying Wang, Yumeng Yang, Yihong Wu. 2014-09-09. Dynamic Control of Local Field Emission Current from Carbon Nanowalls. https://doi.org/10.1116/1.4893540

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