Dopant segregation in YAG single crystal fibers grown by the laser heated pedestal growth technique

•Single crystal fibers of good optical quality were grown by LHPG technique.•Radial dopant segregation in single crystal fiber controlled by growth speed.•Preferential radial segregation of Nd ions compared to Ho ions indicating dependence of segregation on size of dopant.•Sol-gel based technique to add Ho dopants to single crystal YAG fiber is demonstrated.•The calculated Δn due to segregation of Nd ions for such a fiber was determined to be 1.2 × 10−4.