Reflection of Slow Electrons from Graphene on the (110)W Face
M. M. Nishchenko, S. V. Smolnik, M. A. Shevchenko
G.V. Kurdyumov Institute for Metal Physics, NAS of Ukraine, 36 Academician Vernadsky Blvd., UA-03142 Kyiv, Ukraine
Received: 15.07.2014. Download: PDF
The effect of the step-by-step heating in the range of 1300—2800 K under vacuum up to $5\cdot10^{10}$ Pa on both the work function $\varphi$ ($Е = 0-50$ eV) reflection from the (110)W face are studied by the total current spectroscopy and contact potential difference by means of the Anderson method. As revealed, at 2400 K, a monolayer of carbon (graphene) with $\varphi = 5,08 \pm 0,02$ is formed on this face because of segregation of C from a bulk. Increasing the temperature to 2800 K and oxygen treatment remove carbon and form atomically clean (110)W face with $\varphi = 5,30$ eV. Peaks of electron reflection coefficient are observed from these surfaces. As found, their energy position (E) is proportional to the square of the serial number (n) of the peak due to quantum-dimensional effects in the over-barrier electron reflection. For (110)W face, three peaks are observed. With increasing n, their intensities decrease from 45% to 18%, and for graphene, six peaks are observed; intensities of first two peaks drop to 10%.
Key words: graphene, work function, electron reflection coefficient, total current spectroscopy.
URL: http://mfint.imp.kiev.ua/en/abstract/v37/i01/0067.html
DOI: https://doi.org/10.15407/mfint.37.01.0067
PACS: 64.75.St, 65.40.gh, 68.47.De, 68.49.Jk, 68.65.Pq, 73.30.+y, 81.05.ue
Citation: M. M. Nishchenko, S. V. Smolnik, and M. A. Shevchenko, Reflection of Slow Electrons from Graphene on the (110)W Face, Metallofiz. Noveishie Tekhnol., 37, No. 1: 67—78 (2015) (in Russian)