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تسجيل مستخدم جديدRealization of four-state qudits using biphotons
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The novel experimental realization of four-level optical quantum systems (ququarts) is presented. We exploit the polarization properties of frequency non-degenerate biphoton field to obtain such systems. A simple method that does not rely on interferometer is used to generate and measure the sequence of states that can be used in quantum key distribution (QKD) protocol.
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