An electrically pumped VCSEL (10) and a method of its fabrication are presented. The VCSEL (10) comprises an active cavity material (14) sandwiched between top and bottom DBR stacks (12a, 12b), the top DBR (12b) having at least one n-semiconductor layer. The device defines an aperture region (25) between the structured surface (14b) of the active cavity material (14) and the n-semiconductor layer of the top DBR stack (12b). The structured surface (14b) is formed by a top surface of a mesa (22) that includes at least the upper n<++> layer of a p<++>/n<++> tunnel junction and the surface of a p-type layer outside the mesa (22). The structured surface (14b) is fused to the surface of the n-semiconductor layer of the DBR stack (12b) due to the deformation of these surfaces, thereby creating an air gap (24) in the vicinity of the mesa (22) between the fused surfaces. The active region is defined by the current aperture (25) which includes the mesa (22) surrounded by the air gap (24), thereby allowing for restricting an electrical current flow to the active region, while the air gap (24) provides for the lateral variation of the index of refraction in the VCSEL (10).