Orange, red, and near-IR LEDs are often made from GaAs 1x P x solid solutions. For compositions

Question:

Orange, red, and near-IR LEDs are often made from GaAs_1−xP_x solid solutions. For compositions with x < 0.45, a direct band gap is observed, while for larger x the band gap is indirect. Assuming a linear Vegard’s law relationship between the end members GaAs (E_g = 1.43 eV) and GaP (E_g = 2.25 eV), determine the shortest wavelength emitted from a composition with a direct band gap. What color of light would such an LED emit?

Fantastic news! We've Found the answer you've been seeking!