Dr. Siddhartha Das and his student Abhishek Sadhu, Ph.D student at Raman Research Institute, Bangalore published a paper on Testing of quantum nonlocal correlations under constrained free will and imperfect detectors in Physical Review A Journal. Abhishek is the first and also the corresponding author of the paper. Dr. Siddhartha Das is a co-advisor of Abhishek who has been visiting IIIT Hyderabad from time to time. Abhishek will be presenting a poster of this work in-person at 26th Conference on Quantum Information Processing (QIP-2023) being organised by Ghent University, Belgium from 4 – 10 February.
Research work as explained by the authors:
In this work, we deal with the relaxation of two central assumptions in standard locally realistic hidden variable (LRHV) inequalities: free will in choosing measurement settings, and the presence of perfect detectors at the measurement devices. Quantum correlations violating LRHV inequalities are called quantum nonlocal correlations. In principle, in an adversarial situation, there could be a hidden variable introducing bias in the selection of measurement settings, but observers with no access to that hidden variable could be unaware of the bias. In practice, however, detectors do not have perfect efficiency. A main focus of this paper is the introduction of the framework in which given a quantum state with nonlocal behaviour under constrained free will, we can determine the threshold values of detector parameters (detector inefficiency and dark counts) such that the detectors are robust enough to certify nonlocality. We also introduce a class of LRHV inequalities with constrained free will, and we discuss their implications in the testing of quantum nonlocal correlations.
Full paper: https://link.aps.org/doi/10.1103/PhysRevA.107.012212
QIP-2023 Homepage: https://indico.cern.ch/event/1175020/