The role of corners in the second harmonic scattering origin response from silver nanocubes

Fundamental studies on the nonlinear optical properties have been performed over the last years on a series of gold and silver nanoparticles with a special attention to the shape of the nanoparticles [1]. Among many others,... [ view full abstract ]

Fundamental studies on the nonlinear optical properties have been performed over the last years on a series of gold and silver nanoparticles with a special attention to the shape of the nanoparticles [1]. Among many others, nanospheres, nanorods or nanodecahedra have been closely investigated with the determination of their first hyperpolarizability, namely their cross-section for the SHG process [2-4]. A competition between the shape defect contribution and the field multipole modes has been identified while the nonlinearity can be assumed to originate from the surface itself. Unfortunately, no perfect centrosymmetric shape can be achieved and it is difficult to disentangle surface defects from field multipoles. Recently, it has nevertheless been demonstrated how polarization resolved measurements could achieve this operation [5].

To go further into this direction, nanocubes are investigated in the present work. It is indeed expected that, because the six cube facets can be easily identified, the nanocube shape will be close to the ideal shape, perhaps to a larger extend as compared to nanospheres to the spherical shape and nanorods to the ellipsoidal shape for instance.

 We report here the second harmonic scattering (SHS) from silver nanocubes. We discuss the polarization analysis and disentangle the contribution from the surface defects and the field multipoles. These experimental results are presented in light of a surface integral method computations where a particular attention is given to the role of the rounding of edges and corners.

References

[1] J. Butet, P.F. Brevet, O..J.F. Martin,  ACS Nano, 9 (2015) 10545-10562

[2] I. Russier-Antoine, J. Duboisset, G. Bachelier, E. Benichou, C. Jonin, N. Del Fatti, F. Vallée, A. Sánchez-Iglesias, I. Pastoriza- Santos, L.M. Liz-Marzan, P.F. Brevet, J. Phys. Chem. Lett., 1 (2010) 874-880.

[3] I. Russier-Antoine, E. Benichou, G. Bachelier, C. Jonin, P. F. Brevet,J. Phys. Chem. C, 11

[4]    J. Butet, G. Bachelier, I. Russier-Antoine, Ch. Jonin, E. Benichou, P.F. Brevet, Phys. Rev. Lett., 105 (2010) 0774011 (2007) 9044-9048.

[5] Y. El Harfouch, E. Benichou, F. Bertorelle, I. Russier-Antoine, Ch. Jonin, N. Lascoux P.F. Brevet, J. Phys. Chem. C, 118 (2014) 609−616