Ribbon and sheet miniature crystal laser

New types of miniature solid-state lasers with active elements in the form of micron-thick single-crystal ribbons and sheets activated with lanthanide and transition-metal ions are proposed. It is reported that the first crystal used for this purpose was orthorhombic KY(MoO₄)₂:Nd³⁺, lasing at room temperature as a result of the ⁴E_3/2 → ⁴I_11/2 transition when pumped with flashlamps or with lasers.