180 likes | 412 Views
Kubické nelinearity - Kerrov jav. Samomudulacia fázy, samofokusácia. Kerr effect : The refractive index depends upon the intensity of the light propagating through the material. Response. Elmag. wave. Nonlinear medium. Optick ý Kerrov jav.
E N D
Kubické nelinearity - Kerrov jav Samomudulacia fázy, samofokusácia
Kerr effect:The refractive index depends upon the intensity of the light propagating through the material. Response Elmag. wave Nonlinear medium
Elektricky homogénne, izotropné (ε,μ – konštanty) navyše úplne priehľadné čo sa tíka magnetických vlastností (μr = 1). Prostredie je lineárne (platí Ohmov zákon) a nie sú v ňom volné náboje (ρ = 0). ,
E*(z) plus complex conjugate E(z) is constant We expect solution in this form Self-phase modulation
A0 I ρ τ0 t Continuum generation and self-focusing
nel| E(t) |2 z | E(t )|2 | E(t) |2n(t)(t) t t1 t1 t t2 t2 Anti Stokesov posun ω-ωlaser = / t t1 t2 t2 t t t1 Stokesov posun
Δωmax SMF δωM Laser 100 0 200 300 100 200 300 -1 Δω=ω-ω (cm ) laser
Nelineárne médium L/2 -L/2 2/4 π/πLnl Lnl>>z0 L>> z0 nl(0) -L/2 -z0 z0 0 L/2 Nelineárne médium L >> L2 (/ )2 nl( 0) L L2 SMF2ne /0w0 pk,vp = 02/πn2 (p0 / pk,vp)2<< 1 pk,v = 02/2n2 L2 ~ 1.1z0 pk,vl / pk,vp 1.5 (/)2 1
ρ n Self-focusing Nelinearne medium
e) h) b)
b) h) e)