Patent ID: 6317446
Filing Date: 2001-11-13
Classification: H01S

Abstract:
A vertical resonator laser diode, comprisinga laser resonator having a first Bragg reflector layer sequence and a second Bragg reflector sequence, said first and second Bragg reflector layer sequences each having a plurality of mirror pairs;an active layer sequence disposed between said first and second Bragg reflector layer sequences for generating a laser radiation, said active layer sequence having a pumped active region and having a side, one of said first and second Bragg reflector layer sequences being partially transmissive for the laser radiation;a first electrical contact layer and a second electrical contact layer, said first and second Bragg reflector layer sequences and said active layer sequence being disposed between said first and second electrical contact layers;a current aperture provided at least on said side of said active layer sequence for limiting said pumped active region of said active layer sequence by concentrating an operating current flowing through said active layer sequence during a laser operation, said current aperture including aperture layers disposed between one of said first and second electrical contact layers and said active layer sequence, said aperture layers being formed with current passage openings having different sizes, said sizes of said current passage openings increasing in a direction away from said active layer sequence toward one of said first and second electrical contact layers;each of said plurality of mirror pairs including:an Al.sub.z Ga.sub.1-z As mirror layer having a first aluminum content z, a first refractive index n.sub.z and a first thickness d.sub.z ;a further mirror layer having a second refractive index smaller than said first refractive index n.sub.z of said Al.sub.z Ga.sub.1-z As mirror layer, said further mirror layer including an Al.sub.x Ga.sub.1-x As layer and an Al.sub.y Ga.sub.1-y As layer;said Al.sub.x Ga.sub.1-x As layer having a second aluminum content x, a third refractive index n.sub.x and a second thickness d.sub.x ;said Al.sub.y Ga.sub.1-y As layer having a third aluminum content y, a fourth refractive index n.sub.y and a third thickness d.sub.y ;said first aluminum content z being smaller than said third aluminum content y, said third aluminum content y being smaller than said second aluminum content x; andsaid first, second, and third thicknesses d.sub.z, d.sub.x, d.sub.y and said first, third, and fourth refractive indexes n.sub.z, n.sub.x, n.sub.y being dimensioned such that n.sub.x d.sub.x +n.sub.y d.sub.y +n.sub.z d.sub.z.apprxeq..lambda./2, where .lambda. is a laser emission wavelength.