Intensity of Optical Absorption by Excitons

R. J. Elliott
Phys. Rev. 108, 1384 – Published 15 December 1957
PDFExport Citation

Abstract

The intensity of optical absorption close to the edge in semiconductors is examined using band theory together with the effective-mass approximation for the excitons. Direct transitions which occur when the band extrema on either side of the forbidden gap are at the same K, give a line spectrum and a continuous absorption of characteristically different form and intensity, according as transitions between band states at the extrema are allowed or forbidden. If the extrema are at different K values, indirect transitions involving phonons occur, giving absorption proportional to (ΔE)12 for each exciton band, and to (ΔE)2 for the continuum. The experimental results on Cu2O and Ge are in good qualitative agreement with direct forbidden and indirect transitions, respectively.

  • Received 9 April 1957

DOI:https://doi.org/10.1103/PhysRev.108.1384

©1957 American Physical Society

Authors & Affiliations

R. J. Elliott*

  • Physics Department, Reading University, Reading, England

  • *Present address, Clarendon Laboratory, Oxford, England.

References (Subscription Required)

Click to Expand
Issue

Vol. 108, Iss. 6 — December 1957

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review Journals Archive

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×