Anomalous transport of indirect excitons in coupled AlAs/GaAs quantum wells

The time-of-flight method has been used to study the transport of indirect excitons in AlAs/GaAs CQW structures at T greater than or equal to 350 mK and B less than or equal to 14 T. A large increase of the exciton diffusivity is observed at high magnetic fields and low temperatures, when exciton superfluidity is expected to occur.