Long range surface plasmon enhanced reflected second harmonic and fourth harmonic generation in the same fused silica prism

We have observed analytically the long range surface plasmon enhanced reflected second-harmonic-generation and subsequent fourth harmonic generation by reflecting back the generated second harmonic at a required incident angle using a dichroic mirror in the Kretschmann configuration. Enhanced second and fourth harmonic generation are analyzed using the coupled surface plasmon mode in metal–dielectric interfaces formed by a fused silica prism and a liquid dielectric layer which is sandwiched between a prism plane coated with 53 nm thin semi-opaque silver layer and an opaque 200 nm thin silver coated quartz substrate. The enhancement of the generated optical radiation can be explained with the multilayer plane-wave-theory and long range surface plasmon phenomenon.