A theoretical study of laser structures based on dilute-nitride InAsN for mid-infrared operation

Abstract

New dilute-nitride InAsN/GaSb laser diodes on an InAs substrate with a 'W' or 'M' design are theoretically investigated using a ten-band k • p model including valence, conduction and nitrogen-induced bands. For these laser diodes, designed to operate at 3.3 μm at room temperature, optical transition matrix elements for TE and TM modes between the valence sub-bands and the conduction sub-bands, modal gain and total threshold current densities are calculated. Under the hypothesis of a total loss coefficient α = 50 cm −1 , non-conventional 'W' and 'M' multiquantum well laser structures present a calculated threshold current density J th lower than 1.1 kA cm −2 .

Modelling of an InAs/GaSb/InSb short-period superlattice laser diode for mid-infrared emission by the k.p method

“…| e.M n,m (k ρ )| is the optical transition matrix element between the hole subbands and the electron subbands. The final expression for the squared optical matrix is detailed in [23].…”

Effect of strain on $$\hbox {GaAs}_{1-x-y}\hbox {N}_{x}\hbox {Bi}_{y}/\hbox {GaAs}$$ GaAs 1 - x - y

“…Optical gain g(hω) for GaAsNBi/GaAs QWs is calculated by taking into account all the transitions between respective sub-bands as per density matrix theory [27,28]. A conformist method [29] based on the intraband relaxation time (τ in ) approximation convoluted with a Lorentzian function with suitable broadening time (1 × 10 −14 s) is used to evaluate optical gain spectra [30] given as:…”

[h h l]Orientation dependence of optoelectronic properties in InAsN/GaSb quantum well laser diodes with W and M design

“…where J nr , J rad and J aug are, respectively, the nonradiative, radiative and Auger current densities, q is the electron charge, L Z the total thickness of the recombination region equal to N p × L eff , A the Shockley-Read-Hall (SRH) nonradiative recombination coefficient which is related to the defects introducing deep levels into the band gap and has a typical value equal to 10 8 s −1 , B is the spontaneous radiative recombination coefficient found equal to 0.934×10 −11 s −1 cm 3 [16] and C is the nonradiative Auger coefficient extracted from [25] and is equal to 1 × 10 −28 s −1 cm 6 .…”

“…In our previous work, we focused our attention on studying the effects of nitrogen on the band structures and the optical gain for 'W' and 'M' design QW laser structure developed in the [0 0 1] growth axis [14][15][16]. However, the purpose of this paper is to investigate the difference between the electronic and optical properties of the 'W' and the 'M' strained QW laser structures, focusing on comparing the results for the [1 1 0], [1 1 2] and [1 1 3] growth directions with those of the [0 0 1] direction and especially the [1 1 1] direction due to its impact on the optical gain and the threshold current densities of these two QW laser structures 'W' and 'M'.…”