Question

Show that the stimulated emission is not possible for sodium D line at 300°C.

Answer 1

Answer:

Rabi flopping is a sinusoidal population transfer mechanism between two quan-

tum states in which an atom oscillates at Rabi frequency between these states.

Rabi flopping is caused an external electromagnetic field tuned to the frequency

Answer 2

The stimulated emission is not possible for sodium D line at 300°C

Explanation:

The ratio of stimulated emission to spontaneous emission is

$= \frac{Stimulated emission}{Spontaneous emission}$

$= \frac{N_{ST} }{N_{SP} }$

$= \frac{1}{E^{\frac{hv}{KT} } } -1$

Substituting the values,we get      (∵v=c/λ)

$= \frac{1}{exp\left[\begin{array}{ccc}\frac{6.62 *10^{-34}*3*10^{8} }{5,890*10^{-10}*1.38*10^{-23}*573 } \end{array}\right] } -1$

$=\frac{1}{exp\left[\begin{array}{ccc}\frac{19.86*10^{-26} }{4657458.6*10^{-33} } \end{array}\right] } -1$

$=\frac{1}{exp(42.64)-1}$

$=\frac{1}{3.3*10^{18}-1 }$

$=0.303*10^{-18}$

As the ratio is negative it means that spontaneous emission has a greater probabillity than stimulated emission.