Ultrahigh-brightness 850 nm GaAs/AlGaAs photonic crystal laser diodes

Abstract

One-dimensional photonic crystal lasers emitting in the 850 nm range show high internal quantum efficiencies of 93% and very narrow vertical beam divergence of 7.1°͑full width at half maximum͒. 50 m broad area lasers with unpassivated facets exhibit a high total output power of nearly 20 W in pulsed mode with a divergence of 9.5°ϫ 11.3°leading to a record brightness of 3 ϫ 10 8 W cm −2 sr −1 , being presently the best value ever reported for a single broad area laser diode. 100 m broad devices with unpassivated facets show continuous wave operation with an output power of 1.9 W.

High power single-sided Bragg reflection waveguide lasers with dual-lobed far field

“…[8] experimentally demonstrated the narrow FF distribution with FWHM as narrow as 5 • by 16.5-μm-thick Bragg reflector with a mode shape of Shape I, the similar results can also be found in Refs. [7] and [9].…”

“…The dual-lobed or multi-lobed FF patterns were thought as the nature of dual-sided BRL, and attributed to the dualsided transverse Bragg resonance based on the quarter-wave (QtW) Bragg condition [14]. On the contrary, the narrow single-lobed FF patterns were considered as the unique advantage of single-sided BRLs [7][8][9]14]. It seems that the lobe characteristic of FF is determined by the single-sided or dual-sided BRW structure.…”

“…The single-sided BRLs or the so-called longitudinal photonic bandgap crystal (PBC) lasers demonstrate the ultra-narrow vertical beam divergence of about 5-8 • [7][8][9], which are promising for the application of high-brightness lasers. The dual-sided BRLs demonstrate the low threshold (∼157 A/cm 2 ) [10] and high temperature stability [11] with two separated lobes in the vertical far field (FF), which are favored for the phasematched nonlinear BRW [12,13].…”

High-power narrow-vertical-divergence photonic band crystal laser diodes with optimized epitaxial structure

“…The longitudinal PBC lasers have successfully achieved narrow vertical divergence and pulsed output powers of nearly 20 W at various wavelengths. [17][18][19] However, their CW output powers of the single PBC device were usually limited to less than 3 W, even with a stripe width of 100 lm. 17,18 In this paper, we present an optimized design of the longitudinal PBC laser which presents both higher output power and improved vertical divergence compared with our previous results.…”

“…[17][18][19] However, their CW output powers of the single PBC device were usually limited to less than 3 W, even with a stripe width of 100 lm. 17,18 In this paper, we present an optimized design of the longitudinal PBC laser which presents both higher output power and improved vertical divergence compared with our previous results. 20 The performance comparison between laser diodes with and without the PBC structure is also reported, and this will provide a guidance to optimize the PBC laser so as to achieve high-power and high-efficiency laser diodes with narrow vertical divergence.…”