Dielectric function with band theory

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SUMMARY

The dielectric function can be computed using band structure, which is a global property of solids, while the dielectric function itself is a local property. Calculating the dielectric function for specific points, such as on the surface or within the bulk, requires understanding local band structure. The complexity arises from the dependence on both r and r' in non-translationally invariant systems, making it impossible to derive from bulk band structure alone. Fourier transforming yields ε(k), which can be derived from k-dependent Bloch states, with the macroscopic dielectric constant typically reported as ε(k=0).

PREREQUISITES
  • Understanding of band structure theory
  • Familiarity with dielectric function concepts
  • Knowledge of Fourier transforms in solid-state physics
  • Experience with k-dependent Bloch states
NEXT STEPS
  • Research local band structure calculations
  • Study the relationship between dielectric function and band structure
  • Explore literature on non-translationally invariant systems
  • Investigate advanced texts on dielectric functions, such as the book by Maradudin
USEFUL FOR

Physicists, materials scientists, and researchers focused on solid-state physics, particularly those interested in the relationship between dielectric properties and band structure.

taishizhiqiu
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As far as I am concerned, dielectric function can be computed by band structure. However, band structure is a global property of solids, while dielectric function is a local property. How a local property can be computed from a global property.

Put it another way, if I want to calculate dielectric function for a specific point(for example, on the surface or deep in the bulk), how can I do it with band structure? Or there is a concept called local band structure?
 
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The calculation of a dielectric function for non-translationally invariant systems is very complicated as it will depend on both r and r' as ##D(r)=\int dr' \epsilon(r,r') E(r')##(dependence on omega understood) and cannot be done from a bulk band structure. For a point inside the bulk, epsilon will only depend on the distance (r-r') and this dependence decays normally rapidly to zero on a distance of the order of the atomic or lattice spacing.
Fourier transforming gives ##\epsilon(k)## which can be calculated using the k-dependent Bloch states. The macroscopic dielectric constant which is usually reported is epsilon(k=0).
 
DrDu said:
The calculation of a dielectric function for non-translationally invariant systems is very complicated as it will depend on both r and r' as ##D(r)=\int dr' \epsilon(r,r') E(r')##(dependence on omega understood) and cannot be done from a bulk band structure. For a point inside the bulk, epsilon will only depend on the distance (r-r') and this dependence decays normally rapidly to zero on a distance of the order of the atomic or lattice spacing.
Fourier transforming gives ##\epsilon(k)## which can be calculated using the k-dependent Bloch states. The macroscopic dielectric constant which is usually reported is epsilon(k=0).
Can you provide me with some literature?
 
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