sqrtm overleads sqrtm
y = sqrtm(x)
The operator is implemented as a callback operator. It is thus used when you use a general purpose nonlinear solver (such as FMINCON, IPOPT, IPOPT or KNITRO. If you want to obtain a graph-representation using second-order cone constraints, use sqrt instead.
Read more about the difference between sqrt and sqrtm in YALMIP.