PMC HOMEPAGE

GROUPES

Chemistry group Electrochemistry group EPS group Irregularity group

 

Optical pumping in semiconductors

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People involved

Jacques Peretti, Yves Lassailly, Georges Lampel

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The control of electron spin polarization in silicon, the most fundamental microelectronic material, would be a significant advance for spin electronics, or spintronics. In semiconductors, spin can be controlled optically using a phenomenon known as optical injection (discovered in 1968 by Georges Lampel). Although optical injection was first observed in silicon, it has to date only been measured indirectly via the hyperfine coupled nuclear Si²⁹ spin.

In III-V semiconductors, optical injection is usually observed via polarized luminescence or spectroscopic photoemission studies with a Mott polarimeter. These measurment techniques yield a direct, spectroscopic measure of the spin injection in a semiconductor. We are currently applying these techniques to silicon to try an observe for the first time optical spin injection in this material.

EPS has long been active in studies of optical spin injection into III-V semiconductors, and in their application as spin polarized electron sources for nuclear physics experiments.

Selected publications:

• "Highly polarized photoluminescence from 2 µm thick strained GaAs grown on CaF₂"*, L. R. Tessler, C. Hermann, G. Lampel, Y. Lassailly, C. Fontaine, E. Daran, A. Munoz-Yague, Appl. Phys. Lett. 64, 895 (1994).
• "Experimental photoemission investigation of the low energy conduction bands of silicon", Y. Lassailly, P. Chiaradia, C. Hermann, G. Lampel, Phys. Rev. B 41, 1266 (1990).
• "Photoelectronic processes in semiconductors activated to negative electron affinity", C. Hermann, H.-J. Drouhin, G. Lampel, Y. Lassailly, D. Paget, J. Peretti, R. Houdré, F. Ciccacci, H. Riechert, in Spectroscopy of Nonequilibrium Electrons and Phonons, ed. by C.V. Shank, B.P. Zakharchenya (Elsevier Science Publishers, 1992), chap. 9,  p. 397.
• "Photoemission from Activated Gallium Arsenide. I. Very High Resolution Energy Distribution Curves", H.-J. Drouhin, C. Hermann and G. Lampel, Phys. Rev. B 31, 3859 (1985).
• "Photoemission from Activated Gallium Arsenide. II. Spin Polarization Versus Kinetic Energy Analysis", H.-J. Drouhin, C. Hermann and G. Lampel, Phys. Rev. B 31, 3872 (1985).
• "Spin Relaxation of Photoelectrons in p-type Gallium Arsenide", G. Fishman and G. Lampel, Phys. Rev. B 16,  p. 820 (1977).
• "Nuclear Dynamic Polarization by Optical Electronic Saturation and Optical Pumping in Semiconductors", G. Lampel, Phys. Rev. Lett. 20, 491 (1968).

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