arXiv:1503.04697 · Physical Review A

Stronger steerability criterion for more uncertain continuous-variable systems

Priyanka Chowdhury, Tanumoy Pramanik, A. S. Majumdar

Published Oct 14, 2015• 29 citations

Abstract

We derive a fine-grained uncertainty relation for the measurement of two incompatible observables on a single quantum system of continuous variables, and show that continuous-variable systems are more uncertain than discrete-variable systems. Using the derived fine-grained uncertainty relation, we formulate a stronger steering criterion that is able to reveal the steerability of NOON states that has hitherto not been possible using other criteria. We further obtain a monogamy relation for our steering inequality which leads to an, in principle, improved lower bound on the secret key rate of a one-sided device independent quantum key distribution protocol for continuous variables.

DOI: 10.1103/physreva.92.042317

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