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  • Open Access

Detection of quantum imaginarity using moments and its interferometric realization

Sudip Chakrabarty1,*, Saheli Mukherjee1,†, Ananda G. Maity2,‡, and Bivas Mallick1,§,∥

  • *Contact author: sudip27042000@gmail.com
  • †Contact author: mukherjeesaheli95@gmail.com
  • ‡Contact author: anandamaity289@gmail.com
  • §Present address: Statistics and Mathematics Unit, Indian Statistical Institute, 560059 Bangalore, India.
  • ∥Contact author: bivasqic@gmail.com
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APS Open Sci. 1, 000151 – Published 24 September, 2026

DOI: https://doi.org/10.1103/828t-3czf

Abstract

Complex numbers, intrinsic to the formulation of quantum theory, play a pivotal role in enabling advantages across a broad range of quantum information-processing tasks. Despite their fundamental importance, practical and scalable criteria for detecting quantum imaginarity remain relatively underexplored, particularly methods that enable its identification with reduced experimental overhead. In this work, we propose a realistic and experimentally feasible method to detect quantum imaginarity using moment-based approach. Our framework relies on experimentally accessible moments of the Kirkwood-Dirac quasiprobability distribution, enabling scalable detection in high-dimensional systems without requiring full state tomography. We then present illustrative examples to support our detection scheme. Finally, we present an interferometric scheme for measuring these moments, paving the way for experimental implementation of our detection protocol.

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APS Open Sci. 1, 000151– Published 24 September, 2026
Vol. 1
  • Received 9 May 2026
  • Accepted 9 September 2026
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