After prising German star Mesut Ozil away from Real Madrid last season, Arsenal pulled off another transfer coup by completing the signing of Barcelona forward Sanchez on a five-year deal.
Sanchez won six trophies during his three-year spell in Spain and arrives at the Emirates on the back of yet another fourth-placed finish for Arsenal in the Premier League.
Arsenal scored 68 goals in 38 league matches last campaign - their lowest tally since the 2008-09 season - but Arteta says the Chile international will add pace to the club's attack and ease the load on leading striker Oliver Giroud as the club aim to win their first Premier League title since 2004.
"He's the type of player we were looking for," the 32-year-old told Arsenal's official website.
"At some stage [last season] we didn't have that pace up front with the injuries we had, but this year we will. We will be a threat in behind teams and he'll give us another option.
"He's a character, too. He's a fighter and very ambitious. I think he's the type of player that the Arsenal fans will really like.
"It is a very good statement to show where we are going. I think we are going in the right direction, the club is ambitious, the directors are ambitious and we are going to fight for big aims."
Fellow Arsenal midfielder Aaron Ramsey also expressed his excitement following Sanchez's move to London.
"He's a fantastic talent. He's proven it at Barcelona, and at the World Cup he was Chile's main player. I'm sure he'll settle right into this squad and show his quality," Ramsey told Sky Sports News.
"It's a great signing for us and he'll certainly add quality to the team and bring his own style. We're all looking forward to working with him."
