In this video, Menno will introduce the prototypical qubit, the electron spin qubit. He explains how to relate the states of a qubit to the states of the electron spin, along with the behaviour that the spins show under the action of a magnetic field. Moreover, he will also explain how to make use of semiconductor materials as Silicon-28 to isolate electrons to control them for quantum computing.

• A physical qubit can be defined by the states up and down of an electron spin in a magnetic field, where the states are separated by the Zeeman energy. The qubit states 0 or 1 can be defined by the electron spin up or spin down.
• Overtime, in the presence of a magnetic field the spin up acquires a phase relative to the spin down states. It is very important to keep track of this phase to do high-fidelity qubit operation and prevent the decoherence of the qubit overtime.
• To confine a single electron to use it as a qubit semiconductor materials are used, where the interaction of an electron with the lattice can be parametrized to engineer the properties of an electron.
• Heterostructures of silicon and germanium are engineered, to provide an excellent interface where electrons can be confined in the presence of low disorder and where there is no detrimental nuclear spin interaction to build excellent qubits.