METHOD TO PROVIDE A COMMON REFERENCE FRAME BETWEEN TWO RECEIVERS (English)

A method to provide a common reference frame between two receivers, connected via a first transmission channel (10) and a second transmission channel (11) to an entangled photon source (1),wherein the receivers comprise four measurement means to measure the photons each in two mutually unbiased measurement bases,wherein three of the four measurement means comprise a correction means (C1, C2, C3) to set the common reference frame,wherein the method comprises the steps ofi) minimization of the QBER or maximization of the visibility for photons detected in the first (M1) and third (M3) measurement means by adjusting the first correction means (C1) in order to set the same measurement bases between the first measurement means (M1) and the third measurement means (M3),ii) maximization of the QBER or minimization of the visibility for photons detected in the first (M1) and fourth (M4) measurement means by adjusting the second correction means (C2) in order to set mutually unbiased measurement bases between the first measurement means (M1) and the fourth measurement means (M4),iii) minimization of the QBER or maximization of the visibility for photons detected in the fourth (M4) and second (M2) measurement means by adjusting the third correction means (C3) in order to set the same basis between the fourth measurement means (M4) and the second measurement means (M2).