Raman Scattering from Spin — Density Fluctuations in n — Ga As

  • David C. Hamilton
  • A. L. McWhorter


The anomalously large cross sections observed for scattering from single-electron excitations in GaAs can be explained in part as scattering from spin-density fluctuations. The electromagnetic field is coupled to the spins through second-order p∙ A perturbation terms involving the spin-orbit splitting of the valence band. At high carrier densities, where the screening wave vector is much greater than the momentum transfer, the spindensity fluctuations are not screened out as the charge-density fluctuations are, and hence the cross section can be much larger than that due to charge-density fluctuations alone. The polarization properties of the scattered radiation are also different for the two processes. For spin-density scattering the matrix element is proportional to \(\overrightarrow {\sigma \cdot } {\mkern 1mu} \left( {{{\hat \in }_1} \times {{\hat \in }_2}} \right),\) whereas for charge-density scattering it varies as \(\left( {{{\hat \in }_1}\cdot {{\hat \in }_2}} \right),\) where \({\hat \in _1}\) and \({\hat \in _2}\) are the incident and scattered polarization vectors. The magnetic field is taken to be zero throughout.


Density Fluctuation Large Cross Section Integrate Cross Section High Carrier Density Energy Denominator 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    A. Mooradian, Phys. Rev. Letters 20, 11.2 (1968).Google Scholar
  2. 2.
    See, for example, D. Pines, “Elementary Excitations in Solids,” Ch. 3, W.A. Benjamin Inc., New York, 1963.Google Scholar
  3. 3.
    P.A. Wolff, Phys. Rev. 171, 436 (1968).CrossRefGoogle Scholar
  4. 4a.
    R. Loudon, Adv. Physics 13, 423 (1964)CrossRefGoogle Scholar
  5. 4b.
    P.A. Fleury and R. Loudon, Phys. Rev. 166, 514 (1968).CrossRefGoogle Scholar
  6. 5a.
    Y. Yafet, Phys. Rev. 152, 858 (1966)CrossRefGoogle Scholar
  7. 5b.
    P. L. Kelley and G.B. Wright, Bull. Am. Phys. Soc. 11, 812 (1966).Google Scholar
  8. 6.
    E.O. Kane, J. Phys. Chem. Solids 1, 249 (1957).CrossRefGoogle Scholar
  9. 7.
    S. Jha (to be published).Google Scholar
  10. 8.
    R. Loudon, Proc. Roy. Soc. A275, 218 (1963).Google Scholar
  11. 9.
    A.L. McWhorter and P.N. Argyres, paper D-6 this conference.Google Scholar
  12. 10.
    P.A. Wolff, Phys. Rev. Letters 16, 225 (1966).CrossRefGoogle Scholar
  13. 11.
    L. Van Hove, Phys. Rev. 95, 249 (1954).CrossRefGoogle Scholar
  14. 12.
    A. Mooradian, paper D-2 this conference.Google Scholar
  15. 13.
    A. Mooradian and A. L. McWhorter, Phys. Rev. Letters 19, 849 (1967).CrossRefGoogle Scholar
  16. 14.
    A.L. McWhorter, A. Mooradian, and D.C. Hamilton (to be published).Google Scholar

Copyright information

© Springer Science+Business Media New York 1969

Authors and Affiliations

  • David C. Hamilton
    • 1
  • A. L. McWhorter
    • 1
  1. 1.Lincoln LaboratoryMassachusetts Institute of TechnologyLexingtonUSA

Personalised recommendations