Ridge-Type Semiconductor Lasers with Antiguiding Layers for Horizontal Transverse Modes: Dependence on Space in the Antiguiding Layers

Abstract

We consider the Melvin Twist of AdS 5 × S 5 under U(1) × U(1) isometry of the boundary S 3 of the global AdS 5 geometry and identify its field theory dual. We also study the thermodynamics of the Melvin deformed theory.

Simulation of Ridge-Type Semiconductor Lasers with Selectively Proton-Implanted Cladding Layers

“…The kink level peaks at S ¼ 1:98 mm, and the kink level at S ¼ 1:98 mm is 2.54 times as large as that at S ¼ 3:3 mm; 1.58 times as large as the highest value for the ridge structure with optical antiguiding layers. 14) The threshold current for the first-order transverse mode I th1 ¼ I kink , at which a kink appears in the I-L curves, is shown in Fig. 10 as a function of the space between the proton-implanted regions ðSÞ.…”

“…To date, to increase kink level, lossy metal layers, 7) highly resistive regions, 8) a graded V-shape layer, 9) and critical guiding thickness 10) have been studied. To increase kink level and decrease the threshold current further, a ridge structure with optical antiguiding layers have been proposed by the authors, [11][12][13][14] but the fabrication process is fairly complicated.…”

“…From simulations of lasing characteristics, it is found that the kink level is higher and the threshold current is lower than those of the ridge-type semiconductor lasers with optical antiguiding layers for horizontal transverse modes. 14) In addition, the dependences of kink level and threshold current on the space between the protonimplanted regions ðSÞ are analyzed, and it is revealed that they are optimal at S ¼ 1:98 mm. Horizontal and vertical near field patterns are almost independent of S; this result indicates that the light and carriers are confined separately.…”

Simulation of a Ridge-Type Semiconductor Laser with Transversal Diffraction Gratings

“…To achieve high light coupling efficiency between the high power 980-nm semiconductor lasers and the single mode Er 3+ -doped optical fibers, high kink level or kink-free operation of the high power 980-nm semiconductor lasers is needed. To increase the kink level in the ridge structures, lossy metal layers [3], highly resistive regions in both sides of the ridge stripe [4], incorporation of a graded V-shape layer [5], optical antiguiding layers [6,7], separate confinement of carriers and horizontal transverse mode [8], and horizontal coupling of horizontal transverse modes by a groove in the mesa [9] have been studied.…”

Simulation of a ridge-type semiconductor laser with horizontal coupling of lateral modes

“…To date, to increase the kink levels, coupling of the optical field to the lossy metal layers outside the ridge [3], highly resistive regions in both sides of ridge stripe [4], and incorporation of a graded Vshape layer [5] were investigated. To increase the kink level further, a ridge structure with optical antiguiding layers [6], [7] and a ridge structure with separate confinement of carriers and horizontal transverse mode [8] have been proposed. However, kinks have always appeared.…”