The role of nonlinear optical absorption in narrow-band difference-frequency terahertz-wave generation
- Autori: Cherchi, M.; Bivona, S.; Cino, A.; Busacca, A.; Oliveri, R.
- Anno di pubblicazione: 2010
- Tipologia: Articolo in rivista (Articolo in rivista)
- Parole Chiave: Optical frequency conversion, Optical materials, Optical parametric amplifiers, Optical phase matching, Optical propagation in nonlinear media, Optical pulse generation, Optical waveguides, Frequency conversion, Semiconductor materials, Semiconductor waveguides
- OA Link: http://hdl.handle.net/10447/43798
We present a general analysis of the influence of nonlinear optical absorption on terahertz generation via optical difference frequency generation, when reaching for the quantum conversion efficiency limit. By casting the equations governing the process in a suitably normalized form, including either two-photon- or three-photon-absorption terms, we have been able to plot universal charts for phase matched optical-to-terahertz conversion for different values of the nonlinear absorption coefficients. We apply our analysis to some experiments reported to date, in order to understand to what extent multiphoton absorption could have played a role and also to predict the maximum achievable conversion efficiency at higher peak pump intensities.