Question

consider an optical pump at 940nm for yb:yag crystal placed in a cavity. the wavelength of ytterbium is 1030nm. if all the photon emitted by the pump are absorbed by the crystal and used for lasing process. calculate the maximum power output.the pump power is 1 w.

Answer 1

Maximum power output = 0.9126 W

Explanation:

We have longer wavelength and smaller energy at the output.

The lasing wavelength of ytterbium = 1030 nm.

The corresponding frequency and energy for this wavelength is:

νo = c/ λo

and

Eo = hνo = h.( c/λo)

Given that the optical pumping is at higher energy and frequency and shorter wavelength of 940 nm.

νi = c/ λi

Ei = hνi = h.( c/λi)

We know that the time required to pump and the time required to give that energy out is equal in laser. So:

t = Ei/Pi = Eo/Po

  hc / Piλi = hc / Poλo

 Poλo = Piλi

 Po = Piλi / λo

      = 1. 940/1030

      = 0.9126 W