Two‐dimensional model of heat flow in edge‐emitting laser revisited: A new and more versatile approach

Abstract

An analytical, two‐dimensional, stationary model of heat flow in edge‐emitting laser is revisited. In the work, we show how to use this approach to be able to calculate the temperature of the entire device including the most susceptible for thermal runaway region, namely the vicinity of the joint of mirrors and an active layer. Numerical tools based on our considerations are implemented in Matlab code and available at the software developer's web site. A procedure of investigation of surface recombination at facets with the help of our model combined with mirror temperature measurements is proposed. To get an insight in reasonableness of our theoretical research, we calculated temperature profiles and surface recombination velocities for example devices and successfully confronted them with results found in the literature.

From Two- to Three-Dimensional Model of Heat Flow in Edge-Emitting Laser: Theory, Experiment and Numerical Tools

“…Following material data presented in [16], we set v 0 = 4000 m/s, D = 9.6 • 10 −4 m 2 /s, τ = 4 • 10 −9 s and A = 2 • 10 −12 m 3 /s. Additionally, for our structure y 0 = 7 nm (this value is used for calculation of g m and neglected while temperature calculations-see Table 1) and Γ = 0.0065, R = 0.1, v g = 3 • 10 8 /n e f f [m/s], n e f f = 3 are parameters calculated by commercial software [21]. To obtain the most reliable values of T, we decide to take into account the nonideal heat sink.…”

“…Our original concept and related mathematical derivations can be found in [21]. The most important parts of this work are briefly recalled in Sections 2.1 and 2.2, while Section 2.3 is extensive since it contains essential addition, namely, a recipe for calculating current-dependent heating function in axial direction.…”

“…In Ref. [21] we elaborated an original theoretical concept allowing for calculation junction as well as mirror temperatures, and at the same time, avoid the drawbacks mentioned above. We revisited a relatively simple analytical, 2D stationary model of heat flow in an edge-emitting laser.…”

Narrow versus broad waveguide laser diodes: a comparative analysis of self-heating and reliability

“…Several approaches have been proposed to mitigate COD, such as current blocking [9,10], surface passivation [11][12][13], non-absorbing mirrors [14,15], quantum well intermixing [16][17][18][19], and multi-section waveguide design [20][21][22][23]. To study the thermal behavior and heating mechanisms of LDs, various experimental and computational methods have been employed, such as micro photoluminescence [24], Raman spectroscopy [25], infrared scanning near-field optical microscopy [26,27], thermoreflectance spectroscopy [28][29][30][31][32], analytical models [35][36][37][38][39], and numerical simulations [40][41][42][43]. In this paper, we present a combined experimental and numerical investigation of the effect of waveguide width on the temperature and reliability of LDs.…”