Yes, co2 laser can be used under the eyes. However, be very careful to choose a cosmetic physician who has great experience in this specific procedure.
There is the traditional ablative co2 laser which although effective, does carry a fairly significant side effect profile such as scarring and delayed hypopigmentation
Fractional co2 laser can be used with much less risk. It is still a laser procedure being performed in a delicate area so you do want to be conscientious about who you choose to do this. The social downtime is about 5-7 days and final results take upwards of 3 months to fully appreciate (although you will see improvement immediately after healing phase).