1.9 - Multiqubit Systems & Entangles States

The lecture slides are available here Download here.

This lecture explores the importance of multi-qubit systems, introducing the concept of superposition and its parameters. We discuss circle notation for multi-qubit registers, its limitations, and how N qubits can represent 2^N values. Separate circles are used to represent superpositions of N qubits. We cover separable states and tensor product representations.

An entangled state involving three qubits is presented, showcasing its unique properties. Entangled states are emphasized as irreducible at the individual qubit level and not producible solely through single-qubit operations. Lastly, we introduce an approach to multi-qubit circle notation, including binary value labeling and the term "qubyte" for eight-qubit registers, providing a strong foundation for understanding multi-qubit quantum systems and entanglement.