Two-Dimensional Antiguided Vertical Cavity Surface Emitting Laser Arrays With Reflecting Boundary

Abstract

Strong coupling between elements in 2-D resonant antiguided vertical cavity surface emitting laser (VCSEL) arrays results in a good ability to select the in-phase array mode. This ability can be enhanced by proper tailoring of the gain/loss spatial distributions and elimination of lateral radiation loss. To evaluate quantitatively an impact of these means on single-mode stability, numerical simulations are performed for the resonant antiguided VCSEL arrays. A bidirectional beam propagation method was implemented for solving the wave equation in a 3-D scalar diffraction approximation to describe the VCSEL array with reflecting outer boundaries. This structure is composed of distributed Bragg reflectors, active layer, and a thin absorption spacer separated from the active layer. Openings in the top metal electrode pattern the output facet. The above threshold oscillating wave field distribution was calculated. The transverse gain and index distributions were calculated in each quantum well by the 2-D carrier diffusion equation. Stability of single-mode operation against the lasing onset of higher order modes was studied numerically. A parabolic temperature profile was used to imitate thermal focusing. The maximum output power 90 mW for a 5 × 5 array and up to 350 mW for a 10 × 10 array is predicted in the single-mode regime.

Conversion of out-of-phase to in-phase order in coupled laser arrays with second harmonics

“…Phase locking can be achieved with different coupling techniques [11,12]. These include evanescent coupling [13,14], antiguided coupling [15,16], mirrors coupling [17], diffractive coupling with Talbot (or fractional Talbot) cavity [18][19][20], diffractive coupling with self-Fourier cavity [21,22], and diffractive coupling with spatial filtering inside degenerate cavity [23][24][25]. In general, these coupling techniques can result in either positive coupling that tends to lock neighboring lasers with a zero phase shift between them (in-phase locking) [12,14] or negative coupling that tends to lock neighboring lasers with a  phase shift between them (out-of-phase locking) [12][13][14].…”