Fundamentals of PhotonicsBahaa E. A. Saleh, Malvin Carl Teich
송 석 호
Physics Department (Room #36-401)2220-0923, 010-4546-1923, [email protected]
http://optics.hanyang.ac.kr/~shsong
Midterm Exam 30%, Final Exam 30%, Homework 20%, Attend 10%
< 1/4> Course outline
(Supplements)
From Maxwell Eqs to wave equations
Optical properties of materials
Optical properties of metals
< 2/4> Course outline
< 3/4> Course outline
< 4/4> Course outline
Optics
Also, see Figure 2-1, Pedrotti
(Genesis 1-3) And God said, "Let there be light," and there was light.
A Bit of History
1900180017001600 200010000-1000
“...and the foot of it of brass, of the lookingglasses of the women
assembling,” (Exodus 38:8)
Rectilinear Propagation(Euclid)
Shortest Path (Almost Right!)(Hero of Alexandria)
Plane of IncidenceCurved Mirrors(Al Hazen)
Empirical Law of Refraction (Snell)
Light as PressureWave (Descartes)
Law of LeastTime (Fermat)
v
More Recent History
2000199019801970196019501940193019201910
Laser(Maiman)
Quantum Mechanics
Optical Fiber(Lamm)
SM Fiber(Hicks)
HeNe(Javan)
Polaroid Sheets (Land)Phase Contrast (Zernicke)
Holography (Gabor)
Optical Maser(Schalow, Townes)
GaAs(4 Groups)
CO2(Patel)
FEL(Madey)
Hubble Telescope
Speed/Light (Michaelson)
Spont. Emission (Einstein)
Many New Lasers
Erbium Fiber Amp
Commercial Fiber Link (Chicago)
(Chuck DiMarzio, Northeastern University)
Let’s warm-up
일반물리
전자기학
Question
How does the light propagate through a glass medium?
(1) through the voids inside the material.(2) through the elastic collision with matter, like as for a sound.(3) through the secondary waves generated inside the medium.
Construct the wave front tangent to the wavelets
Secondaryon-going wave
Primary incident wave
What about –r direction?
Electromagnetic Waves
0εQAdE =⋅∫
rr
0=⋅∫ AdBrr
dtdsdE BΦ−=⋅∫
rr
dtdisdB EΦμε+μ=⋅∫ 000
rr
Gauss’s Law
No magnetic monopole
Faraday’s Law (Induction)
Ampere-Maxwell’s Law
Maxwell’s Equation
Maxwell’s Equation
Gauss’s Law
No magnetic monopole
Faraday’s Law (Induction)
Ampere-Maxwell’s Law
∫∫∫ ερ
=⋅∇=⋅ dvdvEAdE0
rrrr
0=⋅∇=⋅ ∫∫ dvBAdBrrrr
∫∫∫ ⋅−=⋅×∇=⋅ AdBdtdAdEsdE
rrrrrrr
∫∫
∫∫
⋅εμ+⋅μ=
Φεμ+μ=⋅×∇=⋅
AdEdtdAdj
dtdiAdBsdB E
rrrr
rrrrr
000
000
tEjB∂∂
εμ+μ=×∇r
rrr000
djtE rr
=∂∂
ε0 ( )djjBrrrr
+μ=×∇ 0
0ερ
=⋅∇ Err
⇒
0=⋅∇ Brr
⇒
tBE∂∂
−=×∇r
rr⇒
⇒
⇒
Wave equations
tBE∂∂
−=×∇r
rr
tEB∂∂
=×∇r
rr00εμ
( ) ⎟⎟⎠
⎞⎜⎜⎝
⎛∂∂
−∂∂
=×∇∂∂
=×∇×∇tB
tE
tB
rrrrrr
0000 εμεμ
( ) BB rrrr 2−∇=×∇×∇ kzjyix ˆˆˆ ∂∂
+∂∂
+∂∂
=∇r
( ) ( ) BBBB rrrrrrrr 22 −∇=∇−⋅∇∇=×∇×∇( ) ( ) ( )CBABCACBA rrrrrrrrr ⋅−⋅=××
2
2
002
tBB
∂∂
=∇r
rεμ
2
2
002
tEE
∂∂
=∇r
rεμ
022
002
2
=∂∂
−∂∂
tB
xB εμ
022
002
2
=∂∂
−∂∂
tE
xE εμ
Wave equations
In vacuum
Scalar wave equation
2 2
0 02 2 0x tμ ε∂ Ψ ∂ Ψ− =
∂ ∂
0 cos( )kx tωΨ = Ψ −
02002 =ωεμ−k cvk
≡==00
1εμ
ωSpeed of Light
smmc /103sec/1099792.2 88 ×≈×=
Transverse Electro-Magnetic (TEM) waves
BEtEB
rrr
rr⊥⇒
∂∂
εμ−=×∇ 00
Electromagnetic Wave
Energy carried by Electromagnetic Waves
Poynting Vector : Intensity of an electromagnetic wave
BESrrr
×=0
1μ
2
0
2
0
0
1
1
BcEc
EBS
μ=
μ=
μ=
(Watt/m2)
⎟⎠⎞
⎜⎝⎛ = c
EB
202
1 EuE ε=Energy density associated with an Electric field :
2
021 BuB μ
=Energy density associated with a Magnetic field :
n1n2
Reflection and Refraction
11 θ′=θReflected ray
Refracted ray 2211 sinsin θθ nn =
Smooth surface Rough surface
Reflection and Refraction
00
)()(
)(εμλμε
λλ ==
vcnIn dielectric media,
(Material) Dispersion
Interference & Diffraction
Reflection and Interference in Thin Films
• 180 º Phase changeof the reflected light by a media with a larger n
• No Phase changeof the reflected light by a media with a smaller n
Interference in Thin Films
tn1
Phase change: π
n2 Phase change: π
n2 > n1
λ=λ==δ1
12
nmmt n
Bright ( m = 1, 2, 3, ···)
( ) ( )λ+=λ+==δ1
21
21
12
nmmt n
Bright ( m = 0, 1, 2, 3, ···)
tnPhase change: π
No Phase change
( ) ( )λ+=λ+==δn
mmt n 21
212
λ=λ==δnmmt n2
Bright ( m = 0, 1, 2, 3, ···)
Dark ( m = 1, 2, 3, ···)
Interference Young’s Double-Slit Experiment
Interference
The path difference
λ=θ=δ msind( )λ+=θ=δ 21msind
⇒ Bright fringes m = 0, 1, 2, ····
⇒ Dark fringes m = 0, 1, 2, ····
The phase differenceλ
θπ=π⋅
λδ
=φsind22
θ=−=δ sindrr 12
Hecht, Optics, Chapter 10
Diffraction
Diffraction
Diffraction Grating
Diffraction of X-rays by Crystals
d
θθ
θ
dsinθ
Incidentbeam
Reflectedbeam
λθ md =sin2 : Bragg’s Law
Regimes of Optical Diffraction
d > λ
Far-fieldFraunhofer
Near-fieldFresnel
Evanescent-fieldVector diffraction