The dielectric function of bismuth and the temperature dependence of the band structure parameters

ABSTRACTThe pressure filling of anodic alumina templates with molten bismuth has been used to synthesize single crystalline bismuth nanowires with diameters ranging from 7 to 200nm and lengths of 50μm. The nanowires are separated by dissolving the template, and electrodes are affixed to single Bi nanowires on Si substrates. A focused ion beam (FIB) technique is used first to sputter off the oxide from the nanowires with a Ga ion beam and then to deposit Pt without breaking vacuum. The resistivity of a 200nm diameter Bi nanowire is found to be only slightly greater than the bulk value, while preliminary measurements indicate that the resistivity of a 100nm diameter nanowire is significantly larger than bulk. The temperature dependence of the resistivity of a 100nm nanowire is modeled by considering the temperature dependent band parameters and the quantized band structure of the nanowires. This theoretical model is consistent with the experimental results.

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Temperature dependence of the dielectric function and interband critical points of AlAs obtained on an MBE grown layer

Thin Solid Films ◽

10.1016/0040-6090(93)90072-w ◽

1993 ◽

Vol 233 (1-2) ◽

pp. 122-125 ◽

Cited By ~ 15

Author(s):

M. Garriga ◽

M. Kelly ◽

K. Ploog

Keyword(s):

Temperature Dependence ◽

Dielectric Function ◽

Critical Points ◽

Grown Layer

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Temperature dependence of the dielectric function and critical points of α-SnS from 27 to 350 K

Scientific Reports ◽

10.1038/s41598-020-75383-0 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Hoang Tung Nguyen ◽

Van Long Le ◽

Thi Minh Hai Nguyen ◽

Tae Jung Kim ◽

Xuan Au Nguyen ◽

...

Keyword(s):

Low Temperature ◽

Temperature Dependence ◽

Dielectric Function ◽

Spectral Energy ◽

Phonon Interaction ◽

Electron Phonon Interaction ◽

Temperature Dependences ◽

Exciton Effect ◽

Bose Einstein ◽

Temperature Gradient Method

Abstract We report the temperature dependence of the dielectric function ε = ε1 + iε2 and critical point (CP) energies of biaxial α-SnS in the spectral energy region from 0.74 to 6.42 eV and temperatures from 27 to 350 K using spectroscopic ellipsometry. Bulk SnS was grown by temperature gradient method. Dielectric response functions were obtained using multilayer calculations to remove artifacts due to surface roughness. We observe sharpening and blue-shifting of CPs with decreasing temperature. A strong exciton effect is detected only in the armchair direction at low temperature. New CPs are observed at low temperature that cannot be detected at room temperature. The temperature dependences of the CP energies were determined by fitting the data to the phenomenological expression that contains the Bose–Einstein statistical factor and the temperature coefficient for describing the electron–phonon interaction.

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