A late goal by Eduardo Salvio gave Atletico a narrow advantage to take with them to the Niedersachsenstadion, but Slomka believes his side is capable of overturning that deficit.
And he is going to tell his players to go out and get stuck into their opponents.
"We have got to be more courageous," he said at a press conference.
"We know how strong they are and our respect for them is unaltered, but this time we want to take our chance.
"We know our qualities and our strengths and, if we use them all here at home, then I think we have a chance."
Only Lars Stindl is an injury doubt for Slomka, but Atletico coach Diego Simeone has to do without three suspended players.
Gabi, Arda Turan and Juanfran are all unavailable and Slomka feels their absences increase his side's chance of victory.
"It is more of an advantage because they are three important players and were important in the first leg," he said.
"Atletico can replace them and will be able to replace them quite well, but I think having three players out suspended is not so good for a coach."
Arda Turan and Juanfran are both attack-minded individuals, but Slomka thinks Atletico's philosophy will not change without them.
"I have seen them play often and they rarely had a defensive approach," he said.
"Maybe they will replace their suspended players with more defensive ones, but they will still have at least four attack-minded players on the field."
With Jan Schlaudraff, Didier Ya Konan and Mame Diouf set to start, Slomka will have three attackers in his side, one of whom has developed a reputation for scoring on the big occasion.
Ya Konan's four goals this season have come against Borussia Dortmund, Bayern Munich and Borussia Monchengladbach, and now he wants to add Atletico to that select group.
"For me it's great to score against the top clubs, but the biggest pleasure comes when the team does well," he said.
"I hope that we do well as a team tomorrow [Thursday], and if I get to score a goal, then that would be a bonus."
He could get chances to score too as Atletico coach Diego Simeone has vowed to fight fire with fire and not play a defensive game.
"We would not be well-advised to stick everybody behind the ball as this would play into Hannover's hands," he said.
"Hannover are confident after they got a crucial away goal and we know they are strong at home.
"We have got to find a way of countering them. We know they have got to come at us and we have got to take advantage of that."