The 28-year-old joined the Gunners in Janiary, initially on loan from Southampton. The deal was made permanent last week.
"He's a different quality in the full-back area than what we have," Arteta said.
"He's a gifted, technical player and is probably the best we have in the final third to make the right decision and attack the box as well.
"He can play in a four or a five, he's a really good player with experience in the Premier League that can help us."