Free-Electron Laser Studies of Direct and Indirect 2-Photon Absorption in Germanium
We succeeded in observing the two-photon absorption of germanium for both the direct and the indirect gaps, using the Vanderbilt free-electron laser. The two-photon absorption for the indirect gap was found to be 3 orders of magnitude smaller than the direct gap. The indirect-gap threshold position indicates that the two-photon absorption is assisted by an LO phonon, providing a long-delayed positive test of the Bassani-Hassan predictions.
Vanderbilt univ,dept phys & astron,ctr molec & atom studies surfaces,nashville,tn 37235. Tuncel, e, ecole polytech fed lausanne,inst phys appl,ch-1015 lausanne,switzerland.; ISI Document Delivery No.: LJ827; Times Cited: 23; Cited Reference Count: 18; Cited References: ; 1982, LANDOLTBORNSTEIN A, V17, P87; ASHKINADZE BM, 1968, SOV PHYS SEMICOND, V1, P850; BASSANI F, 1972, NUOVO CIMENTO B, V7, P313; BASSANI F, 1975, ELECTRONIC STATES OP; BRYANT GW, 1980, PHYS REV B, V22, P1992; CATALANO IM, 1974, OPT COMMUN, V11, P254; GIBSON AF, 1976, J PHYS C SOLID STATE, V9, P3259; GOPPERTMAYER M, 1931, ANN PHYS-BERLIN, V9, P273; GROSS EF, 1972, SOV PHYS-SOLID STATE, V14, P368; HASSAN AR, 1973, NUOVO CIMENTO B, V13, P19; LEE CC, 1974, PHYS REV B, V9, P3502; MAHAN GD, 1968, PHYS REV, V170, P825; MCLEAN TP, 1960, PROGR SEMICONDUCTORS, V5, P53; NATHAN V, 1985, J OPT SOC AM B, V2, P294; REINTJES JF, 1973, PHYS REV LETT, V30, P901; TOLK NH, 1991, SPIE P SERIES, V1552, P7; WENZEL RG, 1973, APPL OPTICS, V12, P2245; ZUBOV BV, 1969, PISMA ESKP TEOR FIZ, V9, P130
ISI Document Delivery No.: LJ827
Record created on 2006-10-03, modified on 2016-08-08