scholarly journals Band-structure calculations of Fermi-surface pockets inortho-IIYBa2Cu3O6.5

2007 ◽  
Vol 76 (14) ◽  
Author(s):  
A. Carrington ◽  
E. A. Yelland
2021 ◽  
Vol 103 (8) ◽  
Author(s):  
M. Naumann ◽  
P. Mokhtari ◽  
Z. Medvecka ◽  
F. Arnold ◽  
M. Pillaca ◽  
...  

The Fermi surface of beryllium has been determined experimentally by studying the de Haas–van Alphen effect of single crystals in pulsed magnetic fields. The de Haas–van Alphen frequency (proportional to the extremal area of the Fermi surface normal to the field) was measured as a function of field direction. Consideration of the hexagonal symmetry of the Brillouin zone (discussed in the Appendix) shows that only six distinct classes of fre­quency variation with field direction are possible, and these considerations are used to deduce the locations and forms of the various sheets of the Fermi surface. The Fermi surface is found to consist of hole and electron surfaces of equal volume (each containing 0∙162 carrier per atom). The hole surface is somewhat like a coronet, i. e. a ring of six smoothed tetrahedra joined by small necks lying in the central (0001) plane of the first double Brillouin zone, and the electron surface is a set of six roughly ellipsoidal surfaces (cigars) lying on the vertical edges of the second double zone. Detailed shapes and sizes are deduced for the coronet and cigars such that the extremal areas of cross-section are consistent to within 1 % of those obtained from the observed de Haas–van Alphen frequencies. No oscillations of frequency corresponding to the outer (0001) orbit round the coronet were, however, observed; a study of the field dependence of amplitude of the oscillations from the coupled orbit round the cigar shows that this absence can be explained by magnetic breakdown of the {101̄0} band gap. The model described is in good agreement with the predictions of recent band structure calculations, and is consistent with other experimental evidence.


1980 ◽  
Vol 58 (3) ◽  
pp. 370-375 ◽  
Author(s):  
Z. Altounian ◽  
W. R. Datars

The pressure dependence of the de Haas – van Alphen frequency in oriented potassium samples has been investigated with pressures up to 4.6 kbar. The change of frequency with pressure is less than that expected from free-electron scaling and the Fermi surface anisotropy increases from 0.13% at zero pressure to 0.47% at 4 kbar. These results are discussed in terms of band structure calculations and the charge density wave (CDW) model of potassium. The CDW energy gap changes with pressure for the CDW model to be applicable.


2017 ◽  
Vol 3 (1) ◽  
Author(s):  
Zachary M. Gibbs ◽  
Francesco Ricci ◽  
Guodong Li ◽  
Hong Zhu ◽  
Kristin Persson ◽  
...  

2002 ◽  
Vol 12 (3) ◽  
pp. 483-488 ◽  
Author(s):  
Rustem B. Lyubovskii ◽  
Serguei I. Pesotskii ◽  
Marc Gener ◽  
Roger Rousseau ◽  
Enric Canadell ◽  
...  

1993 ◽  
Vol 07 (01n03) ◽  
pp. 679-682
Author(s):  
E. HOFFMANN ◽  
H. HERPER ◽  
P. ENTEL ◽  
P. MOHN ◽  
K. SCHWARZ

Fixed-spin-moment band-structure calculations of ordered fcc Fe3Ni reveal Fermisurface nesting, which can give rise to a Kohn-like anomaly. This nesting behaviour is very similar to what has recently been seen in nonmagnetic NixAl1–x.1 Using the method of Varma and Weber2 we discuss the renormalized phonon spectrum of Fe3Ni and investigate how the phonon softening and the martensitic transformation depend on the Fermi-surface nesting.


Sign in / Sign up

Export Citation Format

Share Document