Question

A two level laser is possibles in quantum mechanics. How?

Answer 1

Answer:

===>You cannot have 2 level system with the population inversion unless the upper status is metastable and you remove the lower state by some means...

Explanation:

===>Quantum states for energies high enough enough to produce wavelengths of light rather than microwaves are not easy to separate.

===>But it might be possible.

$\mathfrak\red{Thank you}$