Quantum tokens face hurdles to practical use, study finds

Researchers from the Walther-Meißner-Institut, Technical University of Munich, and multiple other German institutions detail hurdles facing quantum tokens in a study published in Quantum Science and Technology on September 1, 2026. The assessment suggests this technology, intended for secure data transmission, is further from widespread application than some projections indicate. The collaborative work, detailed with DOI 10.1088/2058-9565/ae92ad, examines the challenges in building reliable and scalable quantum communication systems. These findings offer a critical perspective on the current state of quantum token development. The foundation for contemporary quantum token concepts originates with Stephen Wiesner’s 1983 proposal, initially envisioning secure quantum banknotes exchangeable between financial institutions and customers. This early work, predating widespread quantum technology, posited a currency reliant on readily verifiable physical states protected from duplication by the laws of quantum mechanics. Four decades later, these foundational ideas have expanded significantly within the quantum information science field, evolving into terms like quantum money, quantum coins, quantum-digital payments, and ultimately, quantum tokens, now moving beyond…