| Electron spins in semiconductor quantum dots have been considered to be the most promising candidates for qubits, the building blocks in a quantum computer and the carriers for quantum information. One particular architecture is based on gate-controlled semiconductor quantum dots which are advantageous for scalability. However, the drawback of this scheme is that the confined electrons interact with nuclear spins in the host semiconductor material, and therefore affect electron spin coherence which is crucial for logic gate control in quantum computing.;A great deal of research has been directed toward improving spin coherence in semiconductor quantum dots. In this dissertation we investigate several problems that are relevant to the coherent manipulation of electron spins in semiconductor quantum dots, such as dynamic nuclear spin polarization and two-electron spin relaxation in double quantum dots. |
