Experimental and numerical determination of coupling constant in a multicore fiber

We report for the first time on measurements of the coupling constant in a multicore fiber at a wavelength of 1.064 mu m. In the multicore geometry th e individual microcores are placed on a ring of 115 mu m diameter inside a pump core. The distance between adjacent cores is about 2.7 mu m while the diameter of each core is approximately 6.9 mu m. The cores are coupled via evanescent fields. The whole system is simulated numerically. The measured coupling constant of 2 c(exp) = 0.82 mm(-1) is in good agreement with the v alue 2c(th) = 0.83 mm(-1) derived from numerical simulations. (C) 2000 Else vier Science mm B.V. All rights reserved.