Secure Continuous Variable Quantum Cloning Based on EPR Steering

Fig. 2. Variation of the steering between entanglement sources ${\hat{b}}_{1}$ and ${\hat{b}}_{2}$ and optimal gain with $η_{1}$ and $η_{2}$ ( $R = 0.5, r = 1.15$ ). (a) Variation of steering of ${\hat{b}}_{2}$ by ${\hat{b}}_{1}$ with $η_{1}$ and $η_{2}$ ; (b) variation of steering of ${\hat{b}}_{1}$ by ${\hat{b}}_{2}$ with $η_{1}$ and $η_{2}$ ; (c) variation of entanglement between ${\hat{b}}_{1}$ and ${\hat{b}}_{2}$ with $η_{1}$ and $η_{2}$ ; (d) variation of the optimal gain with $η_{1}$ and $η_{2}$

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Fig. 3. Fidelity of output models $C l o n e 1$ and $C l o n e 2$ varies with $η_{1}$ and $η_{2}$ where $r = 1.15$ . (a)-(c) Fidelity of $C l o n e 1$ varies with $η_{1}$ and $η_{2}$ when the reflectivity is $0.3, 0.5$ , and $0.7$ respectively; (d)-(f) fidelity of $C l o n e 2$ varies with $η_{1}$ and $η_{2}$ when the reflectivity is $0.3, 0.5,$ and $0.7$ respectively

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Fig. 4. Fidelity of output models $C l o n e 1$ and $C l o n e 2$ varies with $η_{1}$ and $η_{2}$ where $R = 0.5$ . (a)-(c) Fidelity of $C l o n e 1$ varies with $η_{1}$ and $η_{2}$ when the squeezing parameter is $0.35, 0.70,$ and $1.15$ respectively; (d)-(f) fidelity of $C l o n e 2$ varies with $η_{1}$ and $η_{2}$ when the squeezing parameter is $0.35, 0.70,$ and $1.15$ respectively