The defender says he is optimistic the Blaugrana will overcome their Spanish rivals, while he is encouraged by the way the club are coping with their injury problems
The Blaugrana could only manage a 1-1 draw at Camp Nou last week, with Neymar cancelling out Diego's spectacular opener.
However, even though Atletico appear to have the edge going into the return clash in the Spanish capital, Barta believes Barca have what it takes to beat Diego Simeone's side for the first time this season.
"I’m very optimistic," the defender told his club's official website.
"We’ll go all out at the Calderon with the hope of going through to the next round."
Barca will go into the game on the back of a 3-1 victory over Betis that saw them move back to within a point of Liga leaders Atletico.
Tata Martino's men failed to get the crowd going during a laboured victory but Barta was encouraged by the way in which the Catalans coped without injured duo Victor Valdes and Gerard Pique.
“We got a good result against a Betis team that was brave," the 23-year-old centre-half mused.
"We know the fans are on our side and that they want the team to perform well.
“We’ve had bad luck with injuries, but this group has shown that it can overcome delicate situations.
"Now we must overcome this one and do our best [against Atletico].”