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arXiv · 1503.04697

Stronger steerability criterion for more uncertain continuous variable systems

Priyanka Chowdhury·Tanumoy Pramanik·Archan S. Majumdar
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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 stronger steering criterion that is able to reveal the steerability of N00N 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.

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Priyanka Chowdhury, Tanumoy Pramanik, Archan S. Majumdar. 2015-10-16. Stronger steerability criterion for more uncertain continuous variable systems. https://doi.org/10.1103/physreva.92.042317

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