EE424 HW#6
Due: 3/17/2015
A tube 10 cm long with 1-2 cross-sectional area is filled with 1010 two-level atoms with the
transition energy as shown. A laser with a cross-sectional area equal to the tube, and a
frequency close to the resonance frequency of t
EE 424 HW#5
Due: 3/5/2015
1. For the case of a transition in semiconductor, using the formulae for spontaneous and
induced transition rates, calculate the optical intensity I such that the induced transition rate
Wi = A, the spontaneous transition rate. T
EE424 Homework #1
Due in class: 1/19/2016
1. Consider the propagation of a continuous wave laser of wavelength = 500 nm in a glass fiber
of refractive index n = 1.5. Assuming that the laser power (1 Watt) is uniformly distributed
inside the fiber with a d
EE424 HW#6
Due: 3/6/2014
A tube 10 cm long with 1- cross-sectional area is filled with two-level atoms with the transition
energy as shown. A laser with a cross-sectional area equal to the tube, and a frequency close to
the resonance frequency of the atom
EE424 Homework #1
Due: 1/22/2015
1. Derive the ray matrix for a ray entering the following:
(a) a spherical dielectric interface
(b) a plane dielectric interface
(c) Use the result above to get the ray matrix for a thin lens made of spherical surfaces wit
EE424 Homework #1
Due: 1/21/2014
1. Consider the propagation of a continuous wave laser of wavelength = 500 nm in a glass fiber
of refractive index n = 1.5. Assuming that the laser power (1 Watt) is uniformly distributed
inside the fiber with a diameter o
EE424 Homework #4
Due: Feb. 24th 2015
1. The following figure shows the transmission data for a Fabry Perot with the separation and
width of two successive transmission peaks.
Equation 4.7.3: c ~ nl/c[ l + (1-(R1R2)1/2]
3. Complete the derivation of equat
EE424 HW#3
Due: February 4th, 2015
3. Taking into account only modal dispersion, calculate the pulse-width () spreading
experienced by a multimode-laser pulse (= 1 m) propagating in a graded index fiber (length 1
km) with no= 1.5 and g2 = 5 x 103 cm-2 in
EE424 HW#2
Due 1-29-2014
1. Consider a Gaussian laser beam of wavelength 514.5 nm with a minimum spot size o= 2 mm
located at z = 0
(a) At what distance will the beam waist become 1 cm?
(b) What is the radius of curvature of the wavefront at this position
EE 424 HW#9 Solution
2. Please shift = =
2
( )
(a) if = 0 = 0 and the quarter-wave plate provided a phase shift of /2 .
The light becomes circularly polarized, which means the output transmission through the
polarizer is 50%.
(b) To get 100 % transmissio
EE424 HW# 3
Due: 2/4/2016
1. A Gaussian beam with a waist located at z=0, and a wavelength l is incident on a thin lens
placed at z = l as shown below. Find the lens focal length, f, so that the output beam has a waist
located at a given location z = L. S
EE 424 HW#5
Due: 2/27/2014
1. For the case of a transition in semiconductor, using the formulae for spontaneous and
induced transition rates, calculate the optical intensity I such that the induced transition rate
Wi = A, the spontaneous transition rate.
EE424 HW#2
Due 1-28-2014
1. Consider a Gaussian laser beam of wavelength 514.5 nm with a minimum spot size o= 2 mm
located at z = 0
(a) At what distance will the beam waist become 1 cm?
(b) What is the radius of curvature of the wavefront at this position
EE424 Homework #4
Due: Feb. 20th 2014
1. The following figure shows the transmission data for a Fabry Perot with the separation and
width of two successive transmission peaks.
3. Taking into account only modal dispersion, calculate the pulse-width ( ) spr
EE424 HW#7
Due: 4/5/2016
You can assume the refractive index n=1 in this and the following problems, unless otherwise
given.
1. Estimate the critical inversion Nt = (N2-N1) threshold for the 4-level He-Ne laser using the
following parameters
= 632.8 nm
2
EE424 Homework #8
Due: 4/14/2016
1. Mode-locking
A laser cavity containing a gain medium is mode-locked to emit a continuous train of
short pulses. The cavity mirror reflectivities are R1 = 1 and R2 = 0.9. Cavity length is 0.6 m. The
gain medium is a Dopp