Study of singlet excited state absorption spectrum of lutetium bisphthalocyanine using the femtosecond Z-scan technique

In this study we investigate the singlet excited state absorption of lutetium bisphthalocyanine (LuPc2) over a wide spectral range. It was observed distinct nonlinear absorption behaviors; saturable (SA) and reverse saturable absorption (RSA). The RSA effect was observed below 640 and above 680 nm, while SA occurs around the Q-band region, located around 660 nm. To describe the main singlet-singlet transitions, we employed the rate equation model considering the simplified three-energy level diagram. Our results reveal a ratio between excited and ground state absorption smaller than 0.05 at the Q-band region, and of approximately 4 for the other regions. (C) 2012 Elsevier B.V. All rights reserved.

Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)

FAPESP (Fundacao de Amparo a Pesquisa do estado de Sao Paulo)

Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)

CNPq (Conselho Nacional de Desenvolvimento Cientifico e Tecnologico)

Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)

Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)

MCINN

MCINN [AGL 2009-12660/ALI]