Our research explores a foundational shift in the understanding and use of quantum resources. While most quantum information protocols are built around entanglement, we demonstrate that quantum interference—particularly of a single quantum system in spatial superposition—can serve as an independent and powerful resource for information processing [IC1–IC7].

This alternative paradigm enables the development of genuinely quantum protocols that outperform classical counterparts, even in the complete absence of entanglement. By harnessing spatial superpositions and path coherence, we have introduced novel communication and computation schemes, including:

• Two-way communication with a single quantum particle [IC1]
• Quantum-enhanced speed of information acquisition [IC3]
• Universal quantum computation via quantum-controlled classical operations [IC7]

These results open a new line of inquiry in the foundations of quantum information—one where interference, rather than entanglement, plays the central operational role in achieving quantum advantage.

Our work offers both a conceptual alternative and a practical framework for quantum technologies beyond the entanglement-based paradigm.