The Amsterdam giants have completed the transfer of the former Sparta star after already agreeing terms with Heracles for the 23-year-old at the weekend
The Eredivisie champions were in the market for a new midfielder due to the departure of Christian Eriksen to Tottenham last week, and they have snapped up the 23-year-old as his replacement.
Both clubs already reached an agreement over the transfer on Saturday and Duarte has now inked a four-year deal with the Amsterdam side to finalise the move.
Duarte started his professional career with Sparta, but left the Rotterdam side for Heracles in the summer of 2011. He had since become a key player in Almelo, scoring 12 goals in 65 Eredivisie appearances.
The midfielder was called up for Netherlands' Asian tour earlier this summer, but has yet to make his official debut for Oranje.