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All three of these chord comps resolve to the A minor chord. Listen to how different each one sounds when compared to the others. Realize that the difference in mood has very little to do with the fact that they have different rhythms (though that obviously helps).
A Aeolian is just a fancy way of saying “A minor”. So when composing a chord progression in A Aeolian, you use chords that relate to the C major scale: A min – B dim – C maj – D min – E min – F maj – G maj – A min
A Dorian will still treat the Am as “home”, but you use chords that relate to the G major scale instead: A min – B min – C maj – D maj – E min – F# dim – G maj – A min
A Phrygian continues to treat the Am as home, but this mode uses chords that relate to the F major scale: A min – Bb maj – C maj – D min – E dim – F maj – G min – A min