Question

Show that it is possible for stimulated emission to be predominant over spontaneous emission at microwave frequencies at room temperature 300 k

Answer 1

The ratio of the photons emitted by spontaneous and stimulated emissions at temperature can be written as

$R=\exp {\frac {hν}{kT}-1} (1)$

According to formula (1), we can calculate at room temperature (300 K)

R=1.6×10^-3

In this way, stimulated emission dominates over spontaneous emission.