Increase of

$a$

$d$

$N$

The case of the synchronized region unbounded

$d<\frac{4a{\pi }^2}{N^2}$

${\lambda }_2=d$

—

↑

—

$d>\frac{4a{\pi }^2}{N^2}$

${\lambda }_2\approx \frac{4a{\pi }^2}{N^2}$

↑

—

↓

The case of the synchronized region bounded

$d<\frac{4a{\pi }^2}{N^2}$

$R\approx \frac{4a+d}{d}$

↓

↑

—

$d>\frac{4a{\pi }^2}{N^2}$

$R\approx \frac{\left(4a+d\right)N^2}{4a{\pi }^{\text{2}}}$

↑

↓

↓