Preparation Sprinkle tuna with salt and pepper. Heat olive oil in heavy medium skillet over medium-high heat. Add tuna to skillet and cook until brown outside and just opaque in center, about 3 minutes per side. Transfer tuna to plate. Add ginger and garlic to same skillet; stir 30 seconds. Scrape into small bowl. Mix in mayonnaise and lemon juice. Season with salt and pepper. Spread bottoms of rolls with mayonnaise mixture. Top with tuna, arugula and tops of rolls.
Preparation Sprinkle tuna with salt and pepper. Heat olive oil in heavy medium skillet over medium-high heat. Add tuna to skillet and cook until brown outside and just opaque in center, about 3 minutes per side. Transfer tuna to plate. Add ginger and garlic to same skillet; stir 30 seconds. Scrape into small bowl. Mix in mayonnaise and lemon juice. Season with salt and pepper. Spread bottoms of rolls with mayonnaise mixture. Top with tuna, arugula and tops of rolls.