Question
Download Solution PDFPopulation inversion in semiconductor laser diode is achieved by:
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFConcept:
What is population inversion:
“When more atoms exist in higher energy state compare to lower energy state”.
# What is need of population inversion in LASER.
“To perform stimulated emission”
# What is stimulated emission ?
“When on atom in excited state return to the ground state in the presence of photon by emitting another photon which is identical to it in frequency, direction, polarization and phase.
# How the population inversion in semiconductor cases diode occurs?
“By introduction of trap centres on P and n sides”.
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