In:
Japanese Journal of Applied Physics, IOP Publishing, Vol. 35, No. 7A ( 1996-07-01), p. L832-
Abstract:
We have observed resonance second-harmonic generation (SHG) spectra in polydiacetylene (poly [5,7-dodecadiyne-1,12-diyl-bis-ethylurethane], 4U2 for short) films. The resonant peak appears on the high-energy side of the linear absorption peak. The peak observed in SHG spectra is assigned to an A g exciton state, and the linear absorption peak to the lowest B u exciton state. The observation of the dipole-forbidden A g state originates from the resonance enhancement of SHG due to an electric quadrupole transition at the SH frequency region. Thus, the resonance SHG technique serves as a powerful tool for investigating dipole-forbidden states in centrosymmetric media such as π-conjugated polymers. The advantages of this method compared with other methods such as two-photon absorption and electroreflectance will be discussed.
Type of Medium:
Online Resource
ISSN:
0021-4922
,
1347-4065
DOI:
10.1143/JJAP.35.L832
Language:
Unknown
Publisher:
IOP Publishing
Publication Date:
1996
detail.hit.zdb_id:
218223-3
detail.hit.zdb_id:
797294-5
detail.hit.zdb_id:
2006801-3
detail.hit.zdb_id:
797295-7