نام كتاب :PRINCIPLES OF LASERS AND OPTICS

نويسنده :WILLIAM S. C. CHANG

انتشارات : Cambridge University-2005

تعداد صفحات : 247 صفحه

حجم فايل : 1.58 مگابايت

فصول كتاب:

1 Scalar wave equations and diffraction of laser radiation 1
1.1 Introduction 1
1.2 The scalar wave equation 3
1.3 The solution of the scalar wave equation by Green’s
function – Kirchhoff’s diffraction formula 5
1.3.1 The general Green’s function G 6
1.3.2 Green’s function, G1, for U known on a planar
aperture 7
1.3.3 Green’s function for ?U known on a planar
aperture, G2 11
1.3.4 The expression for Kirchhoff’s integral in
engineering analysis 11
1.3.5 Fresnel and Fraunhofer diffraction 12
1.4 Applications of the analysis of TEM waves 13
1.4.1 Far field diffraction pattern of an aperture 13
1.4.2 Fraunhofer diffraction in the focal plane of a lens 18
1.4.3 The lens as a transformation element 21
1.4.4 Integral equation for optical resonators 24
1.5 Superposition theory and other mathematical techniques
derived from Kirchhoff’s diffraction formula 25
References 32

2 Gaussian modes in optical laser cavities and Gaussian beam optics 34
2.1 Modes in confocal cavities 36
2.1.1 The simplified integral equation for confocal cavities 37
2.1.2 Analytical solutions of the modes in confocal cavities 38
2.1.3 Properties of resonant modes in confocal cavities 39
2.1.4 Radiation fields inside and outside the cavity 45
2.1.5 Far field pattern of the TEM modes 46
2.1.6 General expression for the TEMlm modes 46
2.1.7 Example illustrating the properties of confocal
cavity modes 47
2.2 Modes in non-confocal cavities 48
2.2.1 Formation of a new cavity for known modes of
confocal resonators 49
2.2.2 Finding the virtual equivalent confocal resonator for a
given set of reflectors 50
2.2.3 Formal procedure to find the resonant modes in
non-confocal cavities 52
2.2.4 Example of resonant modes in a non-confocal cavity 53
2.3 Gaussian beam solution of the vector wave equation 54
2.4 Propagation and transformation of Gaussian beams
(the ABCD matrix) 57
2.4.1 Physical meaning of the terms in the Gaussian
beam expression 57
2.4.2 Description of Gaussian beam propagation by
matrix transformation 58
2.4.3 Example of a Gaussian beam passing through a lens 61
2.4.4 Example of a Gaussian beam passing through
a spatial filter 62
2.4.5 Example of a Gaussian beam passing through a
prism 64
2.4.6 Example of focusing a Gaussian beam 66
2.4.7 Example of Gaussian mode matching 67
2.5 Modes in complex cavities 68
2.5.1 Example of the resonance mode in a ring cavity 69
References 71

3 Guided wave modes and their propagation 72
3.1 Asymmetric planar waveguides 74
3.1.1 TE and TM modes in planar waveguides 75
3.2 TE planar waveguide modes 77
3.2.1 TE planar guided wave modes 77
3.2.2 TE planar guided wave modes in a symmetrical
waveguide 78
3.2.3 Cut-off condition for TE planar guided wave modes 80
3.2.4 Properties of TE planar guided wave modes 81
3.2.5 TE planar substrate modes 83
3.2.6 TE planar air modes 83
Contents vii
3.3 TM planar waveguide modes 85
3.3.1 TM planar guided wave modes 85
3.3.2 TM planar guided wave modes in a symmetrical
waveguide 86
3.3.3 Cut-off condition for TM planar guided wave modes 87
3.3.4 Properties of TM planar guided wave modes 87
3.3.5 TM planar substrate modes 89
3.3.6 TM planar air modes 89
3.4 Generalized properties of guided wave modes in
planar waveguides and applications 90
3.4.1 Planar guided waves propagating in other directions in
the yz plane 91
3.4.2 Helmholtz equation for the generalized guided wave
modes in planar waveguides 91
3.4.3 Applications of generalized guided waves in
planar waveguides 92
3.5 Rectangular channel waveguides and effective
index analysis 98
3.5.1 Example for the effective index method 102
3.5.2 Properties of channel guided wave modes 103
3.5.3 Phased array channel waveguide demultiplexer
in WDM systems 103
3.6 Guided wave modes in single-mode round optical
fibers 106
3.6.1 Guided wave solutions of Maxwell’s equations 107
3.6.2 Properties of the guided wave modes 109
3.6.3 Properties of optical fibers 110
3.6.4 Cladding modes 111
3.7 Excitation of guided wave modes 111
References 113

4 Guided wave interactions and photonic devices 114
4.1 Perturbation analysis 115
4.1.1 Fields and modes in a generalized waveguide 115
4.1.2 Perturbation analysis 117
4.1.3 Simple application of the perturbation analysis 119
4.2 Coupling of modes in the same waveguide, the grating filter
and the acousto-optical deflector 120
4.2.1 Grating filter in a single-mode waveguide 120
4.2.2 Acousto-optical deflector, frequency shifter, scanner
and analyzer 125
4.3 Propagation of modes in parallel waveguides – the coupled
modes and the super-modes 130
4.3.1 Modes in two uncoupled parallel waveguides 130
4.3.2 Analysis of two coupled waveguides based on modes of
individual waveguides 131
4.3.3 The directional coupler, viewed as coupled individual
waveguide modes 133
4.3.4 Directional coupling, viewed as propagation of
super-modes 136
4.3.5 Super-modes of two coupled non-identical waveguides 137
4.4 Propagation of super-modes in adiabatic branching waveguides
and the Mach–Zehnder interferometer 138
4.4.1 Adiabatic Y-branch transition 138
4.4.2 Super-mode analysis of wave propagation in a
symmetric Y-branch 139
4.4.3 Analysis of wave propagation in an asymmetric
Y-branch 141
4.4.4 Mach–Zehnder interferometer 142
4.5 Propagation in multimode waveguides and multimode
interference couplers 144
References 148

5 Macroscopic properties of materials from stimulated
emission and absorption 149
5.1 Brief review of basic quantum mechanics 150
5.1.1 Brief summary of the elementary principles
of quantum mechanics 150
5.1.2 Expectation value 151
5.1.3 Summary of energy eigen values and energy states 152
5.1.4 Summary of the matrix representation 153
5.2 Time dependent perturbation analysis of ? and the
induced transition probability 156
5.2.1 Time dependent perturbation formulation 156
5.2.2 Electric and magnetic dipole and electric quadrupole
approximations 159
5.2.3 Perturbation analysis for an electromagnetic field with
harmonic time variation 159
5.2.4 Induced transition probability between
two energy eigen states 161
5.3 Macroscopic susceptibilty and the density matrix 162
5.3.1 Polarization and the density matrix 163
5.3.2 Equation of motion of the density matrix elements 164
5.3.3 Solutions for the density matrix elements 166
5.3.4 Susceptibility 167
5.3.5 Significance of the susceptibility 168
5.3.6 Comparison of the analysis of ? with the quantum
mechanical analysis of induced transitions 169
5.4 Homogeneously and inhomogeneously broadened transitions 170
5.4.1 Homogeneously broadened lines and their saturation 171
5.4.2 Inhomogeneously broadened lines and their saturation 173
References 178

6 Solid state and gas laser amplifier and oscillator 179
6.1 Rate equation and population inversion 179
6.2 Threshold condition for laser oscillation 181
6.3 Power and optimum coupling for CW laser oscillators with
homogeneous broadened lines 183
6.4 Steady state oscillation in inhomogeneously broadened lines 186
6.5 Q-switched lasers 187
6.6 Mode locked laser oscillators 192
6.6.1 Mode locking in lasers with an inhomogeneously
broadened line 193
6.6.2 Mode locking in lasers with a homogeneously
broadened line 196
6.6.3 Passive mode locking 197
6.7 Laser amplifiers 198
6.8 Spontaneous emission noise in lasers 200
6.8.1 Spontaneous emission: the Einstein approach 201
6.8.2 Spontaneous emission noise in laser amplifiers 202
6.8.3 Spontaneous emission in laser oscillators 205
6.8.4 The line width of laser oscillation 207
6.8.5 Relative intensity noise of laser oscillators 210
References 211

7 Semiconductor lasers 212
7.1 Macroscopic susceptibility of laser transitions
in bulk materials 214
7.1.1 Energy states 215
7.1.2 Density of energy states 215
7.1.3 Fermi distribution and carrier densities 216
7.1.4 Stimulated emission and absorption and susceptibility
for small electromagnetic signals 218
7.1.5 Transparency condition and population inversion 221
7.2 Threshold and power output of laser oscillators 221
7.2.1 Light emitting diodes 223
7.3 Susceptibility and carrier densities in quantum well
semiconductor materials 224
7.3.1 Energy states in quantum well structures 225
7.3.2 Density of states in quantum well structures 226
7.3.3 Susceptibility 227
7.3.4 Carrier density and Fermi levels 228
7.3.5 Other quantum structures 228
7.4 Resonant modes of semiconductor lasers 228
7.4.1 Cavities of edge emitting lasers 229
7.4.2 Cavities of surface emitting lasers 234
7.5 Carrier and current confinement in semiconductor lasers 236
7.6 Direct modulation of semiconductor laser output by
current injection 237
7.7 Semiconductor laser amplifier 239
7.8 Noise in semiconductor laser oscillators 242
References 243

Index