All-optical signal processing in quadratic nonlinear materials

David Moss

Sirona Valdueza‐Felip, F. B. Naranjo, Miguel González‐Herráez +7 more

We characterize the third order nonlinear optical response of the interband transition of bulk InN and the intraband transition of GaN/AIN quantum dots, both of them in the spectral region around 1.5 mufrac14m. The results show that these materials can be very suitable for optical signal processing applications in the spectral region of wavelength-division multiplexed (WDM) transmission. Considering the temporal behavior of the nonlinear response, InN seems particularly useful in all-optical control of light speed (slow-light generation), whereas GaN/AIN quantum dots are promising for switching and wavelength conversion applications.

L. Lefort, Alain Barthélémy

The scope of this paper is to revisit the use of quadratic crystals cut for second harmonic generation (SHG) with type II phase-matching in view of all-optical processing of light signal. The investigations on this topic mainly focused in the past years on the possibilities opened by cascading of quadratic nonlinearities in phase-mismatched conditions [1]. The goal of this paper is to remind the reader that various types of optical processing are achievable with sum and difference frequency generation in phase-matched position without the requirement for cascaded nonlinearities. In a first part we will report few examples of the use of difference frequency generation (or down conversion) for signal processing. In a second part we will show that type II SHG with unbalanced fundamental inputs may lead to coherent amplification or transistor like operation.

Elaheh Tahmasebi, Elham Yousefi, Mohsen Hatami +1 more