| 摘要 |
A quantum memory device comprises a quantum dot molecule having two aligned and coupled quantum dots 3, 7 configured to store a photogenerated exciton which can be generated in one of two spin eigenstates or in a superposition of the eigenstates to define a qubit. The exciton may be modulated by an electric field applied to the contact electrodes 17, 19 so that the excitons electron and hole are either in the same quantum dot direct configuration state or in different quantum dots which is an indirect configuration state. The switching between the direct and indirect configurations is conducted in accordance with a relationship between the applied electric field and the fine structure splitting of the exciton. The quantum memory device may be utilised in quantum information processing systems such as quantum repeaters and quantum networks which require the quantum state of a photon to be mapped onto a stable quantum memory. |
