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Wox
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Elastic scattering from a bound electron is classically described by considering the driven, damped harmonic oscillator model for the motion of a bound electron in a classical em-wave. The (non-relativistic) equation of motion is written as
[tex]
m\frac{d^{2}\bar{x}}{dt^{2}}=q\bar{E}(t,\bar{x})-m\omega_{0}^{2}\bar{x}-m\gamma\frac{d\bar{x}}{dt}
[/tex]
where the effect of the magnetic field is neglected. For a monochromatic plane wave [itex]\bar{E}(t,\bar{x})=\bar{E}_{0}e^{i(\bar{k\cdot\bar{x}}-\omega t)}[/itex] the solution is given by
[tex]
\bar{x}(t)=e^{-\frac{\gamma}{2}t}(C_{1}e^{Ct}+C_{2}e^{-Ct})-\frac{q\bar{E}_{0}}{m(\omega^{2}-\omega_{0}^{2}+ \omega\gamma i)}e^{i(\bar{k\cdot\bar{x}}-\omega t)}
[/tex]
where [itex]C=\sqrt{\frac{\gamma^{2}}{4}-\omega_{0}^{2}}[/itex], [itex]C_{1}[/itex] and [itex]C_{2}[/itex] constants depending on the boundary conditions, [itex]\omega_{0}[/itex] is the resonance frequency of the harmonic oscillator and [itex]\gamma[/itex] the damping coefficient. (The first part is known as the transient solution and the second as the steady state solution.)
Now what would be the solution for unpolarized light?
[tex]
m\frac{d^{2}\bar{x}}{dt^{2}}=q\bar{E}(t,\bar{x})-m\omega_{0}^{2}\bar{x}-m\gamma\frac{d\bar{x}}{dt}
[/tex]
where the effect of the magnetic field is neglected. For a monochromatic plane wave [itex]\bar{E}(t,\bar{x})=\bar{E}_{0}e^{i(\bar{k\cdot\bar{x}}-\omega t)}[/itex] the solution is given by
[tex]
\bar{x}(t)=e^{-\frac{\gamma}{2}t}(C_{1}e^{Ct}+C_{2}e^{-Ct})-\frac{q\bar{E}_{0}}{m(\omega^{2}-\omega_{0}^{2}+ \omega\gamma i)}e^{i(\bar{k\cdot\bar{x}}-\omega t)}
[/tex]
where [itex]C=\sqrt{\frac{\gamma^{2}}{4}-\omega_{0}^{2}}[/itex], [itex]C_{1}[/itex] and [itex]C_{2}[/itex] constants depending on the boundary conditions, [itex]\omega_{0}[/itex] is the resonance frequency of the harmonic oscillator and [itex]\gamma[/itex] the damping coefficient. (The first part is known as the transient solution and the second as the steady state solution.)
Now what would be the solution for unpolarized light?
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