Novel method for preparing high-indistinguishable coherent states

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Novel method for preparing high-indistinguishable coherent states

St. Petersburg Polytechnical University Journal: Physics and Mathematics. 2022. Vol. 15. No. 3.3. P. 198–201.

Gerasin I. S., Mekhtiev E. E., Maksimova E. L., Rudavin N. V., Duplinsky A. V., Kurochkin Y. V.

The preparation of indistinguishable quantum states by remote users is one of the crucial tasks in MDI-QKD. To solve this problem, laser injection techniques or modulation of the CW laser on the transceiver side are used. These techniques require a complex setup or a pair of modulators. Here we present a different setup for generating coherent states, using one modulator and one gain-switched laser per transceiver, to find a balance between the complexity of the setup and its cost. The level of indistinguishability achieved allows our scheme to be used in high-speed MDI-QKD protocols.

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