Controlling the dopant profile for SRH suppression at low current densities in λ ≈ 1330 nm GaInAsP light-emitting diodes

The quantum efficiency of double hetero-junction light-emitting diodes (LEDs) can be significantly enhanced at low current density by tailoring the spatial profile of dopants to suppress Shockley–Read–Hall recombination. To demonstrate this effect, we model, design, grow, fabricate, and test a GaInAsP LED ( λ ≈ 1330 nm) with an unconventional dopant profile. Compared against that of our control design, which is a conventional n+-n-p+ double hetero-junction LED, the dopant profile near the n-p+ hetero-structure of the design displaces the built-in electric field in such a way that the J02 space charge recombination current is suppressed. The design principle generalizes to other material systems and could be applicable to efforts to observe and exploit electro-luminescent refrigeration at practical power densities.