Nanowire-based multiple quantum dot memory

The authors propose and demonstrate an alternative memory concept in which a storage island is connected to a nanowire containing a stack of nine InAs quantum dots, each separated by thin InP tunnel barriers. Transport through the quantum dot structure is suppressed for a particular biasing window due to misalignment of the energy levels. This leads to hysteresis in the charging/discharging of the storage island. The memory operates for temperatures up to around 150K and has write times down to at least 15ns. A comparison is made to a nanowire memory based on a single, thick InP barrier.