Both goals in the first leg in Madrid came from penalties, with striker Viktor Gyokeres scoring for Arsenal and Julian Alvarez converting for Atletico.
"They are available, both in the squad. Great, because we need options and the capacity to play in the squad," Arteta told reporters on Monday.
Arsenal, who top the Premier League table with three games remaining, were knocked out at the semi-final stage of the Champions League last season by eventual winners Paris St Germain.
"I can't wait. I feel the energy in and around the team," Arteta said.
"Together we have done a lot of work as a club and as a team. They have been waiting a long time to have this kind of night. Something amazing can happen."
Meanwhile, Atletico manager Diego Simeone said his side had changed hotels ahead of the return leg in London after staying elsewhere during their 4-0 league-phase defeat by Arsenal, joking that the decision was down to cost, despite Spanish media reports suggesting superstition.
"We're better off now than we were in October. And the hotel was cheaper. That's why we changed," Simeone said with a laugh.
On the injury front, Alvarez - who has 20 goals and nine assists in 48 matches across all competitions this season - was included in Atletico's travelling squad after being replaced late in the first leg and emerging as an injury doubt.
The 26-year-old Argentine World Cup winner previously played for Manchester City.
"Julian in this type of game is important," Simeone said. "He knows the league very well. Last week's game was very good. I hope that tomorrow he can respond in the way the game wants."