Mathematical Models for Nano Science - Politecnico di Milano
Mathematical Models for Nano Science - Politecnico di Milano
Mathematical Models for Nano Science - Politecnico di Milano
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Model equations - 1<br />
• Exciton<br />
equation<br />
⎧<br />
∂X<br />
∂t + <strong>di</strong>v J X = G − X τ X<br />
⎪⎨<br />
∂X<br />
∂t + <strong>di</strong>v J X = G − X −<br />
X + ηk rec P<br />
τ X τ <strong>di</strong>ss<br />
J X = −D X ∇X<br />
in Ω n ∪ Ω p<br />
in Ω H<br />
in Ω<br />
X = 0<br />
on Γ C ∪ Γ A<br />
⎪⎩<br />
X (x, 0) = X 0 (x) in Ω.<br />
• Excitons have null net charge → Only <strong>di</strong>ffusion (Fick law)<br />
• Generation term G(x, t): constant, Beer-Lambert<br />
• Exciton lifetime τ X , geminate pair <strong>for</strong>mation time τ <strong>di</strong>ss<br />
• Geminate pair recombination rate constant k rec and triplet<br />
exciton fraction η<br />
• X and J X are continuous in Ω