Simultaneous measurement of the two-photon coefficient and free-carrier cross section above the bandgap of crystalline silicon
- 1 February 1986
- journal article
- Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE Journal of Quantum Electronics
- Vol. 22 (2) , 360-368
- https://doi.org/10.1109/jqe.1986.1072964
Abstract
We report what is to our knowledge the first simultaneous measurement of the two-photon absorption coefficient and the free-carrier cross section above the bandgap in a semiconductor. This is also the first observation of two-photon absorption of 1 μm radiation in single-crystal Si at room temperature in a regime where a two-photon stepwise process involving indirect absorption followed by free-carrier absorption is usually dominant. A critical pulsewidth (and fluence) is established below (and above) which two-photon absorption cannot be neglected. Pulses that range from 4 to 100 ps in duration are then used to isolate the irradiance-dependent two-photon absorption from the fluence-dependent free-carrier absorption. We obtain an indirect two-photon absorption coefficient of 1.5 cm/GW and extract a free-carrier cross section of 5 \times 10^{-18} cm 2 by using a simple technique that does not require a knowledge of the actual carrier density.Keywords
This publication has 24 references indexed in Scilit:
- Various phase transitions and changes in surface morphology of crystalline silicon induced by 4–260-ps pulses of 1-μm radiationApplied Physics Letters, 1984
- Optical multistability in silicon observed with a cw laser at 1.06 μmOptics Communications, 1983
- Universal behavior of exchange-correlation energy in electron-hole liquidPhysical Review B, 1982
- Computer modeling of the temperature rise and carrier concentration induced in silicon by nanosecond laser pulsesJournal of Applied Physics, 1982
- Optical absorption in heavily doped siliconPhysical Review B, 1981
- High-efficiency degenerate four-wave mixing of 106-μm radiation in siliconOptics Letters, 1979
- Determination of the interband and the free carrier absorption constants in silicon at high-level photoinjectionJournal of Physics D: Applied Physics, 1979
- Two-photon absorption in semiconductors with picosecond laser pulsesPhysical Review B, 1976
- Picosecond optoelectronic switching and gating in siliconApplied Physics Letters, 1975
- Three-Photon Stepwise Optical Limiting in SiliconPhysical Review Letters, 1967