In a bowl, blend the butter, lemon juice, ginger, and chives well. Set aside at room temperature.
Heat the oven to 500°F. Set a large ovenproof skillet over medium-high heat and add just enough oil to make a light film. Sprinkle the salmon lightly with salt and pepper. When the oil is very hot, add the salmon, skin side up, and cook until nicely browned, about 1 min. Flip the fish over and put the skillet in the oven. Roast for 2 min. for medium rare; 4 min. for medium well. Check for doneness with the tip of a knife. Remove the pan from the oven, transfer the fish to serving plates, and immediately top the salmon with a dab of the lemon-ginger butter.