  We study chaotic-integrable transition and the nature of quantum chaos in SYK
model with chemical potential. We use a novel numerical technique to calculate
the partition function explicitly. We show the phase transition in the presence
of large chemical potential. We also show that a mass-like term consisting of
two fermion random interaction (q=2 SYK term) does not give rise to a sharp
transition. We find that turning on the chemical potential suppresses the
Lyapunov exponent in the chaotic phase exponentially.
