Phys. Rev. B 65, 165335 (2002) [17 pages]Binding energy of charged excitons in ZnSe-based quantum wellsReceived 2 November 2001; published 12 April 2002 Excitons and charged excitons (trions) are investigated in ZnSe-based quantum well structures with (Zn,Be,Mg)Se and (Zn,Mg)(S,Se) barriers by means of magneto-optical spectroscopy. Binding energies of negatively (X-) and positively (X+) charged excitons are measured as functions of quantum well width, and free carrier density and in external magnetic fields up to 47 T. The binding energy of X- shows a strong increase from 1.4 to 8.9 meV with decreasing quantum well width from 190 to 29 Å. The binding energies of X+ are about 25% smaller than the X- binding energy in the same structures. The magnetic field behavior of X- and X+ binding energies differ qualitatively. With growing magnetic field strength, X- increases its binding energy by 35–150%, while for X+ it decreases by 25%. Zeeman spin splittings and oscillator strengths of excitons and trions are measured and discussed. © 2002 The American Physical Society URL:
http://link.aps.org/doi/10.1103/PhysRevB.65.165335
DOI:
10.1103/PhysRevB.65.165335
PACS:
73.21.Fg, 71.10.Ca, 71.35.-y, 78.66.Hf
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