Getting empty plot?

Questions
,
1
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2

Ehsan,

there is something wrong with the power symbols you are using, e.g. \chi 1 (in FullForm) contains TextCell["2"]. Instead try this:

\[Chi]1 = -((4 \[Beta] (\[CapitalDelta]c - \[CapitalDelta]p\
) (\[CapitalDelta]p (\[CapitalDelta]c - \[CapitalDelta]p) + \
\[CapitalOmega]c^2))/((\[CapitalDelta]c - \[CapitalDelta]p)^2\
 (\[CapitalGamma]c^2 + 4 \[CapitalDelta]p^2) + \[Zeta]d + 
       4 \[CapitalOmega]c^4));
\[Chi]2 = ((2 \[Beta] \[CapitalGamma]c (\[CapitalDelta]c - \
\[CapitalDelta]p)^2)/((\[CapitalDelta]c - \[CapitalDelta]p)^2\
 (\[CapitalGamma]c^2 + 4 \[CapitalDelta]p^2) + \[Zeta]d + 
      4 \[CapitalOmega]c^4));
3

With corrected syntax:

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