The band structure of aluminium I. Determination from experimental data

The band structure and particularly the shape of the Fermi surface are deduced mainly from the available experimental data on the de Haas-van Alphen and anomalous skin effects, and from the low-temperature specific heat. Since these data are rather incomplete, it is found necessary to use in conjunction with them a theoretical band-structure calcula­tion, which, however, unavoidably contains rough approximations. Except near the surface of.the Brillouin zone, E (k) is found to be very close to the free-electron energy. The first zone is found to contain 3.6 × 10 -3 holes per atom around the zone comers. There is overflow of electrons into the second zone across all the zone faces, and these regions of the Fermi distribution are joined together near the centres of the zone edges; the third zone contains a very small number of electrons.

2015 ◽  
Vol 29 (25n26) ◽  
pp. 1542014 ◽  
Author(s):  
M. Shimizu ◽  
Y. Moriya ◽  
S. Baar ◽  
N. Momono ◽  
Y. Amakai ◽  
...  

We performed low-temperature specific heat measurements on slightly underdoped samples of monolayer cuprate superconductors [Formula: see text] (Ln = La, Eu, Ln-Bi2201) under magnetic fields [Formula: see text]. In La-Bi2201, the coefficient [Formula: see text] of [Formula: see text]-linear term in the electronic specific heat [Formula: see text] at [Formula: see text] shows [Formula: see text] dependence, as expected in [Formula: see text] -wave superconductors. In Eu-Bi2201, [Formula: see text] shows almost the same [Formula: see text] dependence as that of La-Bi2201 below [Formula: see text] T, while [Formula: see text] is suppressed above [Formula: see text] T and deviates downward from the [Formula: see text] curve of La-Bi2201. This result suggests the the gap and the electronic excitation spectrum near nodes are modified in Eu-Bi2201 except the region of the Fermi surface in the immediate vicinity of nodes.


2007 ◽  
Vol 21 (14) ◽  
pp. 885-891 ◽  
Author(s):  
NUPINDER KAUR ◽  
N. K. GAUR ◽  
R. K. SINGH

We have applied the Rigid Ion Model (RIM) to study the cohesive and thermal properties of binary intermetallic BeB 2 and TiB 2. The paper reports the calculated results on cohesive energy (ϕ), compressibility (β), molecular force constant (f), Restrahalen frequency (ν0), Debye temperature (Θ D ) and Gruneisen parameter (γ) for the temperature range 50 K ≤ T ≤ 300 K and the effect of van der Waal interaction on these properties are also shown. Our results on Debye temperature are closer to the experimental data. In addition, we have computed the specific heats for BeB 2 and TiB 2 and compared them with the available experimental data.


2015 ◽  
Vol 11 (3) ◽  
pp. 3224-3228
Author(s):  
Tarek El-Ashram

In this paper we derived a new condition of formation and stability of all crystalline systems and we checked its validity andit is found to be in a good agreement with experimental data. This condition is derived directly from the quantum conditionson the free electron Fermi gas inside the crystal. The new condition relates both the volume of Fermi sphere VF andvolume of Brillouin zone VB by the valence electron concentration VEC as ;𝑽𝑭𝑽𝑩= 𝒏𝑽𝑬𝑪𝟐for all crystalline systems (wheren is the number of atoms per lattice point).


2017 ◽  
Vol 86 (8) ◽  
pp. 084601 ◽  
Author(s):  
Tetsuji Okuda ◽  
Hiroto Hata ◽  
Takahiro Eto ◽  
Shogo Sobaru ◽  
Ryosuke Oda ◽  
...  

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