A Cauchy problem for minimal spacelike surfaces in $\mathbb{R}^4_2$

We give a definition of isoclinic parametric surfaces in $\mathbb{R}^4_2$ and prove that such an isoclinic conformal immersion comes from two holomorphic functions. A Cauchy problem was proposed and solved, namely: construct an isoclinic and minimal positive (negative) spacelike surface in $\mathbb{R}^4_2$, containing a given positive (negative) real analytic curve. At last, we study the important and well-known Bj\"orling problem, providing some examples was given in the last section.