Patent ID: 8254213

Claim:
A near-field light generating device comprising: a substrate; a semiconductor laser device which is formed on the substrate and emits laser light polarized in a first direction; a light absorbing device which is formed on the substrate to be close to a light emission facet of the semiconductor laser device and absorbs light polarized in a second direction orthogonal to the first direction; and a near-field light generator which is formed on the substrate to be close to a light emission part of the light absorbing device, wherein an active layer of the semiconductor laser device and an absorption layer of the light absorbing device both have a quantum well structure, in which (a) when a well layer in the active layer is strain-free or has a compression strain in a direction perpendicular to the confinement direction of the quantum well, a well layer in the absorption layer has a tensile strain in a direction perpendicular to the confinement direction of the quantum well, and (b) when the well layer in the active layer has a tensile strain in a direction perpendicular to the confinement direction of the quantum well, the well layer of the absorption layer has a compression strain in a direction perpendicular to the confinement direction of the quantum well.