An atomizer provides a high-quality fuel-air mixture to a gas turbine engine, by combining air input from an engine compressor and fuel input from a single low-pressure fuel supply pump. The atomizer includes an atomizer body, a main vortex chamber, a secondary vortex chamber for improving quality of the fuel-air mixture, and a fuel sleeve providing fuel to the secondary vortex chamber. The main vortex chamber includes a main outlet nozzle in fluid communication with a combustion chamber inlet of the gas turbine engine. The secondary vortex chamber includes a secondary outlet nozzle in fluid communication with the main vortex chamber. The fuel sleeve has a blind channel with a longitudinal axis and a fuel tip. The same atomizer may be used for startup mode and for all operational modes of the gas turbine engine.