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Determine the total carrier recombination lifetime of a double heterojunction LED where the radioactive and nonradioactive recombination lifetime of minority carriers in active region are 70 ns and 100 ns respectively.

Determine the total carrier recombination lifetime of a double heterojunction LED where the radioactive and nonradioactive recombination lifetime of minority carriers in active region are 70 ns and 100 ns respectively. Correct Answer 41.17 ns

The total carrier recombination lifetime is given by τ = τrτnr/τr+τnr = 70× 100/70 + 100 ns = 41.17 ns Where τr = radiative recombination lifetime of minority carriers τnr = nonradioactive recombination lifetime of minority carriers.

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