English

Robust certification of quantum instruments through a sequential communication game

Quantum Physics 2026-02-17 v2

Abstract

We propose a communication game in the sequential measurement scenario, involving a sender and two receivers with restricted communication among the latter parties. In the framework of the prepare-transform-measure scenario, we find a prominent quantum advantage in the receiver's decoding of the message originally encoded by the sender. We show that an optimal trade-off between the success probabilities of the two receivers enables self-testing of the sender's state preparation, the first receiver's instruments, and the measurement device of the second receiver in a semi-device-independent way. Our protocol enables a more robust certification of the unsharp measurement parameter of the first receiver compared to an earlier protocol. We further generalize our game to higher-dimensional systems, revealing greater quantum advantage with an increase in dimensions.

Keywords

Cite

@article{arxiv.2506.12946,
  title  = {Robust certification of quantum instruments through a sequential communication game},
  author = {Pritam Roy and Subhankar Bera and A. S. Majumdar and Shiladitya Mal},
  journal= {arXiv preprint arXiv:2506.12946},
  year   = {2026}
}

Comments

10+5 pages, 11 figures, close to published version

R2 v1 2026-07-01T03:18:38.603Z