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. Fig, La courbe du bas correspond au bruit sur la différence des photocourants. La puissance totale du faisceau pompe est de l'ordre de 15 mW, ce qui permet de ne pas saturer la détection. 6. ´ Etude au-dessus du seuil D.2 Résultats expérimentaux Nous avons effectué plusieurs mesures, ` a diverses fréquences d'analyse. Pour les fréquences au-dessous de 20 MHz, la valeur du critère EPR est améliorée grâcè a la cavité de filtrage, mais il n'est pas dépassé pour autant. Les faisceaux sont inséparablesinséparablesà partir d'une fréquence d'analyse légèrement inférieurè a 6 MHz. Les faisceaux produits sont EPRàEPRà une fréquence d'analyse de 20 MHz. La puissance des faisceaux EPR mesurés est de 5 mW. Il est sans doute possible d'en obtenir de plus brillants mais la détection homodyne saturant audeì a de cette puissance

. Fig, Mesure, lorsque la cavité de filtrage est présente, de la quadrature la moins bruitée pour A + (bleu ciel) et A ? (bleu foncé), et séparabilité. Le système fonctionne au-dessus du seuil, la fréquence d'analyse est de 20 MHz

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