In this paper, we present a novel representation of two-qubit systems using three Bloch spheres. We explicitly construct a bijection between the Hilbert space of state vectors and a triple-sphere framework, where the first two Bloch spheres encode the individual qubit states, and the third sphere captures the entanglement between them. This geometric interpretation provides intuitive insights into the structure of composite quantum systems and lays the groundwork for further generalization to n-qubit systems. This work is the first step in a broader line of research aimed at developing a Bloch-sphere-based model to describe and analyze the behavior of multi-qubit systems, with a special focus on the study of entanglement.
Franco, C., De La Cruz, H.I., Pelayo, F.L., Javier Paulet, J., Mezzini, M., Pascual, V., et al. (2025). QC–HORIZON 2025 proceedings: Quantum Informatics, Computing & Technology 2025. In QC–HORIZON 2025 Quantum Informatics, Computing & Technology 2025 (pp.53-62) [10.24132/csrn.qc.2025-a0].
QC–HORIZON 2025 proceedings: Quantum Informatics, Computing & Technology 2025
Mauro Mezzini;
2025-01-01
Abstract
In this paper, we present a novel representation of two-qubit systems using three Bloch spheres. We explicitly construct a bijection between the Hilbert space of state vectors and a triple-sphere framework, where the first two Bloch spheres encode the individual qubit states, and the third sphere captures the entanglement between them. This geometric interpretation provides intuitive insights into the structure of composite quantum systems and lays the groundwork for further generalization to n-qubit systems. This work is the first step in a broader line of research aimed at developing a Bloch-sphere-based model to describe and analyze the behavior of multi-qubit systems, with a special focus on the study of entanglement.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
