Question

Ques 4 A solid laser produces light of wavelength 11600 Angstrom at room temperature. 
Determine the frequency of the emitted radiation. 
Determine the energy difference between two energy levels emitting this radiation in Joule  
Determine the energy difference between two energy levels emitting this radiation in eV  
Which pumping technique is preferred in solid laser? 
What is lifetime of metastable state? ​

Answer 1

" is an acronym for Light Amplification by Stimulated Emission of Radiation. Lasers are finding ever increasing military applications -- principally for target acquisition, fire control, and training. These lasers are termed rangefinders, target designators, and direct-fire simulators. Lasers are also being used in communications, laser radars (LIDAR), landing systems, laser pointers, guidance systems, scanners, metal working, photography, holography, and medicine.

In this document the word laser will be limited to electromagnetic radiation emitting devices using light amplification by stimulated emission of radiation at wavelengths from 180 nanometers to 1 millimeter. The electromagnetic spectrum includes energy ranging from gamma rays to electricity. Figure 1 illustrates the total electromagnetic spectrum and wavelengths of the various regions.

Answer 2

Answer:

The frequency of the emitted light is $2.58×10^{14} Hz$. The energy difference in Joule is $1.7079×10^{-19} J$. The energy difference in eV is 1.067 eV. The three level pumping technique is followed. The lifetime of metastable state is 10 millisecond.

Explanation:

Laser

The full form of laser is light amplification by stimulated emission of radiation. In this light is amplified using stimulated emission process. In stimulated emission a photon is striked to excited state of the electron. This photon emits the other photon from the excited electron. So, by this process we have a plenty of photons which helps is the formation of light of laser.

Now, it is given that wavelength of light is given by 11600 Angstrom or $11600×10^{-10} m$.

The frequency of light υ is given by

υ = c/λ

where c is the speed of light$= 3×10^{8} m/s$. So, frequency $υ = (3×10^{8})/(11600×10^{-10}) = 2.58×10^{14} Hz$.

The energy difference of the levels is the energy of light emitted. So, energy difference is

E = hυ

where h is Planck's constant. The

$E = (6.62×10^{-34})×(2.58×10^{14}) = 1.7079×10^{-19} J$

In eV energy difference is

$E = (1.7079×10^{-19})/(1.6×10^{-19}) = 1.067 eV$

In solid state laser the three level pumping scheme is followed. In three level pumping scheme, there are three levels and the electron jumps from the higher level to the second level. After that it comes to first level. The second and first level transition is of laser transition.

Metastable state

Metastable state is a state in which electron takes large time to stay than other states. In solid laser the time for metastable state is 10 millisecond.