We have investigated the magnetotransport properties of ultrathin films of Bi grown on thermally oxidized Si(001) substrates with thickness ranging from 10 to 100 nm at temperatures down to 2 K and in magnetic fields up to 90 kOe. Remarkable differences both in temperature and field dependence of the Hall resistivity are found for the films with thickness above and below 20 nm. These observations can be explained due to the presence of surface states, which play an important role in determining the electronic transport properties of the thinnest films. The estimated surface carrier density 4 x 10^(13) cm^(-2) at room temperature correlates well with that recently reported from angle-resolved photoemission spectroscopy on ultrathin Bi(001) films.
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机译：我们已经研究了在热氧化的Si（001）衬底上生长的Bi超薄膜的磁输运特性，该衬底的厚度范围从10到100 nm，温度低至2 K，磁场强度高达90 kOe。对于厚度大于或小于20nm的膜，发现在温度和霍尔电阻率的场相关性方面的显着差异。由于存在表面状态，可以解释这些观察结果，这些表面状态在确定最薄薄膜的电子传输性能中起着重要作用。室温下估计的表面载流子密度为4 x 10 ^（13）cm ^（-2）与最近从超薄Bi（001）薄膜上的角度分辨光发射光谱学报告的结果非常相关。
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