Normalized atomic susceptibility (χaFM) , an upper bound to the participation ratio PR 1 of the first excited state, for N = 303 (empty red circles) and N = 610 (blue triangles) as a function of normalized disorder strength. The solid black line shows the corresponding simulation results for χ a,1 of equation ( 3 ). The black dotted line is the directly simulated participation ratio of PR 1 . The inset shows the maximum value of the zero-disorder atomic susceptibility as a function of atom number, showing linear scaling expected from the definition of χ a (equation ( 15 )). Data are obtained from a fit of the polariton’s response ± standard deviation, with different atom numbers. The fitted data are averaged over 290 measurements for N = 303 (empty red circles) and over 269 measurements for N = 610 (blue triangles). For the inset, data are obtained from a fit of the polariton’s response ± standard deviation, with different atom numbers. The fitted data are averaged over 19 measurements.
