Which of the following is essential for laser action to occur between two energy levels of an atom?
A)the lower level is metastable
B)the upper level is metastable
C)the lower level is the ground state
D)the are more atoms in the lower level than in the upper level
E)the lasing material is a gas

Question

Quizplus · Accepted Answer

For laser action to occur, the upper energy level must be metastable, allowing for a population inversion where more atoms are in the excited state than in the lower energy state. This condition is crucial for stimulated emission, the process that amplifies light in a laser.

Which of the Following Is Essential for Laser Action to Occur