We report on the design and the fabrication of 1D photonic crystal nanobeam cavities with optical resonances around 800\&\#x00A0;nm, compatible with rubidium, cesium, or argon atomic transitions. The cavities are made of indium gallium phosphide material, a III-V semi-conductor compound which has a large index of refraction (n\&\#x2243;3.3) favoring strong optical confinement and small mode volumes. Nanobeam cavities with inline and side coupling have been designed and fabricated, and quality factors up to 2\&\#x00D7;104 have been measured.