Rosa Letizia's main research interests are focused on the area of Computational Modelling of artificial materials such as Photonic Band Gap (PBG) structures, linear and nonlinear, and Metamaterials for potential application into scaled-down particle accelerators and nano-photonics in general. She is also currently interested in the use of these composite materials for the exploitation of highly dispersive structures such as plasmonic waveguides in new frequency ranges of application. As a contribution to this field, Rosa Letizia has recently proposed a generalised MRTD scheme including a dispersion model of the complex refractive index of metals through various mathematical models such as Drude, Drude-Lorentz, and Drude-Critical Points model.

She serves as a regular reviewer for the most prestigious journals in photonics such as IEEE/OSA Journal of Lightwave Technology, IEEE Photonics Technology Letters, IEEE Journal of Quantum Electronics, IET Optoelectronics, Journal of Applied Optics, Journal of Optical and Quantum Electronics, Progress in Electromagnetic Research and many others.