EFFECTS OF THE INTERACTION BETWEEN LOCALIZED SURFACE PLASMONS AND RARE-EARTH ION BASED SOLID-STATE GAIN MEDIA

 

E. Yraola, P. Molina, M. O Ramírez and L.E. Bausá^*

Dept. Física de Materiales and Instituto de Ciencia de Materiales NicolUniversidad Autónoma de Madrid, 28049-Madrid, Spain

 

 

The manipulation of light-matter interaction phenomena at the nanoscale by means of plasmonic nanostructures gives rise to a variety of unique effects that are currently the subject of an intense research activity from both fundamental and technological point of view. These effects relay in the ability of plasmonic nanostructures to strongly concentrate the electromagnetic field in the vicinity of their physical boundaries, enhancing the interactions between optical species (atoms, QDs, organic fluorophores, etc) and far-field light [1,2].

 Here, periodic arrays of Ag nanoparticles are photochemically assembled in chain-like form on the ferroelectric domain walls of Nd³⁺ doped periodically poled LiNbO₃ laser crystals [3]. The coupling between the optical transitions of Nd³⁺ ions and the localized surface plasmon resonances supported by the metallic nanostructures results in a directional and periodic intensification of the Nd³⁺ emission. The mechanism of enhancement is analyzed taking into account the different polarization configurations [4].  

On the other hand, the implications of the plasmonic coupling on the laser parameters of the solid-state gain medium are evaluated to show a dramatic reduction of the pump power at the laser threshold. The results constitute a promising approach for gain-enhanced nanoplasmonic metamaterials, as well as for rare earth based nanolasers operating at the subwavelength scale.

 

 

 

[1] W. L. Barnes, A. Dereux and T. W. Ebbesen, Nature 424 (2003) 824.

[2] L. Novotny, N. van Hulst, Nature Photonics 5, (2011) 83.

[3] E. Yraola, P. Molina, J. L. Plaza, M. O Ramírez and L. E. Bausá, Advanced Materials 25 (2013) 910.

[4] P. Molina, E.Yraola, M. O Ramírez, J. Plaza, C. de las Heras, L. E. Bausá,  Nano Letters  13 (2013) 4931.