Intraband and interband processes in the infrared spectrum of metallic aluminum

Journal Article · Wed Oct 15 04:00:00 EDT 1986 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.34.5191· OSTI ID:5193310

Smith, D Y; Segall, B

The dielectric function of polycrystalline metallic aluminum derived by Shiles et al. (Phys. Rev. B 22, 1612 (1980)) from room-temperature ultrahigh-vacuum reflectance measurements has been analyzed into intraband and interband components and compared with theoretical predictions of Szmulowicz and Segall (Phys. Rev. B 24, 892 (1981)). For this analysis, a new approach was developed, which utilizes experimental data over a larger energy range than in previous studies. To within experimental uncertainty, the resulting intraband component is consistent with a Drude model having a plasma frequency ..cap omega../sub p/ = 12.5 +- 0.3 eV and relaxation time tau = (1.06 +- 0.12) x 10/sup -14/ sec. These values are in accord with the bulk static conductivity which in turn is in agreement with the inertial sum rule on the real part of the dielectric function. The interband contribution was found to consist of a broad background with two superimposed peaks: the well-known ''0.8 ..mu..m'' absorption at --1.5 eV and a weaker absorption in the vicinity of 0.4 eV. This interband spectrum is in good agreement in regard to both peak position and oscillator strength with the one-electron augmented-plane-wave model calculations for the optical conductivity by Szmulowicz and Segall. The total experimental intraband and interband oscillator strengths for the conduction electrons are 1.9 and 1.2 electrons/per atom, respectively.

• Research Organization: Materials Science and Technology Division, Argonne National Laboratory, Argonne, Illinois 60439
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 5193310
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 34:8; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
ALUMINIUM
CRYSTALS
DIELECTRIC PROPERTIES
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELEMENTS
EQUATIONS
INFRARED SPECTRA
MEDIUM TEMPERATURE
METALS
OPTICAL PROPERTIES
OSCILLATOR STRENGTHS
PHYSICAL PROPERTIES
POLYCRYSTALS
SPECTRA
SUM RULES
ULTRAHIGH VACUUM