Towards quantum teleportation with quantum-dot spin qubits

Electron spins in quantum dots are a promising building block for quantum computing. While fundamental gate operations on single and two qubits have been demonstrated, quantum algorithms utilizing three or more qubits have not tested so far. Quantum teleportation is one of the important milestones that can be implemented with three qubits, because it explicitly makes use of quantum entanglement and is applicable to quantum communication and quantum computing. The key of Quantum teleportation is to prepare one of maximally entangled states and perform projection measurement onto them. These can be, in principle, implemented by using a two-qubit gate operation and a series of single-qubit operations. However, realization of those controls remains challenging in three-spin-qubit systems. Instead, the Pauli spin blockade can be utilized to prepare and selectively measure one of the maximally entangled state. This significantly simplifies partial implementation of the quantum teleportation protocol.