Thermo-optic effect and optical third order nonlinearity in nc-Si embedded in a silicon-nitride film.
Using a self-diffraction experiment with 7ns pulses at 532nm we studied a silicon nitride film containing silicon nanoclusters (nc-Si) of 3.1+/-0.37 nm mean size. The sample was prepared by remote plasma-enhanced chemical vapor deposition (RPECVD), and we found that its nonlinearity consists of a combination of electronic and thermal contributions. By varying the repetition rate of the laser, we discriminated the responsible mechanisms for the nonlinear response. Using this procedure we determined a total /chi((3))1111/ = 3.3x10(-10)esu, n2 = 2.7x10(-16) m(2)/W, beta = 1x10(-9) m/W and dn/dT =1x10(-4) degrees C(-1) for our sample. We also show results for the optical Kerr effect using 80 fs pulses at 820 nm. The purely electronic nonlinearity measured is characterized by /chi((3))1111/=9.5 x10(-11) esu.
Torres-Torres
C
C
Sección de Estudios de Posgrado e Investigación-ESIME-IPN, Zacatenco, México DF, México. crstorres@yahoo.com.mx
López-Suárez
A
A
Tamayo-Rivera
L
L
Rangel-Rojo
R
R
Crespo-Sosa
A
A
Alonso
J C
JC
Oliver
A
A