Luminescence properties of excitons in the asymmetric coupled quantum dots under electric fields

We theoretically analyzed the bonding and anti-bonding energy states in the GaAs/Al_0.35Ga_0.65As asymmetric coupled quantum dots under a series of electric fields. The carrier tunneling effect strongly influences the exciton energy and oscillator strength. We find that energy splitting of anti-crossing occurs under an critical electric field for hole bounding and anti-bonding states, and both the energy gap and the critical field decrease with increasing the barrier distance. Meanwhile, the exciton luminescence intensity changes from bright(dark) to dark(bright) under external fields.