Optical Second-Harmonic Generation with Surface Plasmons in Silver Films

Theory of the giant plasmon-enhanced second-harmonic generation in graphene and semiconductor two-dimensional electron systems

“…Moreover, at the oblique incidence of radiation one can resonantly excite the 2D plasma waves in the system (e.g. in the attenuated total reflection geometry) which would lead to the resonant enhancement of the higher harmonics 21 . In this paper we theoretically study the second-order nonlinear electromagnetic response of two-dimensional electron systems, including both graphene and conventional 2D structures with the parabolic electron energy dispersion.…”

Enhanced third harmonic generation from the epsilon-near-zero modes of ultrathin films

“…Frequency-mixing from interfaces and thin nonlinear films has also been intensely investigated since the early days of nonlinear optics 8,9 , with several studies exploiting the field enhancement associated with the excitation of short 10 and long 11 range surface plasmon polaritons 12 . More recently, intriguing light-matter interactions occurring in natural or artificial epsilon-near-zero (ENZ) materials have come under scrutiny.…”

Laser-launched evanescent surface plasmon polariton field utilized as a direct coherent pumping source to generate emitted nonlinear four-wave mixing radiation

“…Here we should mention that similar processes using SPPs to serve as the input waves have already been experimentally demonstrated in the coupling of optical SHG to SPPs in thin silver films [10], the surface CARS of the benzene/silver system [14], and the surface 4WM at the air/gold interface using only incident optical fields as the pumping sources [18,19], all of which feature SPP fields by themselves acting as input waves, without extra optical fields interacting with them, to yield the desirable enhanced output of SHG, CARS, or 4WM. However, the concept developed here features optically launched SPP field acting as a direct pumping source that coherently interacts with an extra propagating optical field to generate another outgoing optical field (the emitted 4WM radiation in this particular case).…”

“…Noticeably, the coherent nature of the evanescent SPP surface wave [1, 2,8] has recently been "visualized" in a straightforward fashion in an elegant "double-slit" experiment with SPPs [9]. It is thus expected that SPPs may, in principle, be able to participate directly (and coherently) in conventional nonlinear optical processes of fundamental and practical interest, such as second-harmonic generation (SHG) [10][11][12][13], coherent anti-Stokes Raman scattering (CARS) [14], and four-wave mixing (4WM) [15][16][17][18][19][20][21].…”