Introduction to Optics Introduction to Optics

Introduction to Optics Introduction to Optics

Lecture homepage : http://optics.hanyang.ac.kr/~shsong/syllabus-Optics-Part I.html Professor : 송석호, shsong@hanyang.ac.kr, 02-2220-0923 (Room# 36-401)

Textbook : 1. Frank L. Pedrotti, "Introduction to Optics", 3rd Edition, Prentice Hall Inc.

2. Eugene Hecht, "Optics", 2nd Edition, Addison-Wesley Publishing Co.

Evaluation : Attend 10%, Homework 10%, Mid-term 40%, Final 40%

(Genesis 1-3) And God said, "Let there be light," and there was light.

Also, see Figure 2-1, Pedrotti

Optics Optics

www.optics.rochester.edu/classes/opt100/opt100page.html

빛의 역사

저자

번역

김옥수

Introduction to Optics

Introduction to Optics – – 3rd 3rd

A Bit of History A Bit of History

1900 1800

1700

1600 2000

1000 0

-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 Incidence Curved Mirrors (Al Hazen)

Empirical Law of Refraction (Snell)

Light as Pressure Wave (Descartes)

Law of Least Time (Fermat)

v<c, & Two Kinds of Light (Huygens)

Corpuscles, Ether (Newton)

Wave Theory (Longitudinal) (Fresnel)

Transverse Wave, Polarization Interference (Young)

Light & Magnetism (Faraday) EM Theory (Maxwell)

Rejection of Ether, Early QM (Poincare, Einstein)

(Chuck DiMarzio, Northeastern University)

More Recent History More Recent History

2000 1990

1980 1970

1960 1950

1940 1930

1920 1910

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)

Lasers

Lasers

Nature of Light Nature of Light

• • Particle Particle

–– Isaac Newton (1642Isaac Newton (1642--1727)1727) –– OpticsOptics

• • Wave Wave

–– Huygens (1629Huygens (1629--1695)1695) –– Treatise on Light (1678)Treatise on Light (1678)

• • Particle, again Particle, again

–– Planck (1900), Einstein (1905)Planck (1900), Einstein (1905)

• • Wave Wave - - Particle Duality Particle Duality

–– De De BroglieBroglie (1924)(1924)

Maxwell -- Electromagnetic waves

Planck

Planck ’ ’ s hypothesis (1900) s hypothesis (1900)

•• Light as particlesLight as particles

•• Blackbody Blackbody –– absorbs all wavelengths and conversely emits absorbs all wavelengths and conversely emits all wavelengths

all wavelengths

•• Light emitted/absorbed in discrete units of energy (quanta),Light emitted/absorbed in discrete units of energy (quanta), E = n h f

E = n h f

•• Thus the light emitted by the blackbody is,Thus the light emitted by the blackbody is,

⎟⎟ ⎠

⎞

⎜⎜ ⎝

⎛

= −

1 1

) 2

(

2

hc kT

e M hc

λ

λ π

Photoelectric Effect (1905) Photoelectric Effect (1905)

•• Light as particlesLight as particles

•• EinsteinEinstein’’s (1879s (1879--1955) explanation1955) explanation

–– light as particles = photonslight as particles = photons

Kinetic energy = hƒ - Ф

Electrons Light of frequency ƒ

Material with work function Ф

Wave Wave - - particle duality (1924) particle duality (1924)

•• All phenomena can be explained using either All phenomena can be explained using either the wave or particle picture

the wave or particle picture

•• Usually, one or the other is most convenientUsually, one or the other is most convenient

•• In In PHYSICAL OPTICSPHYSICAL OPTICS we will use the wave we will use the wave picture predominantly

picture predominantly

p

= h

λ

Photons and Electrons Photons and Electrons

Nanophotonics, Paras N. Prasad, 2004, John Wiley & Sons, Inc., Hoboken, New Jersey., ISBN 0-471-64988-0

Both photons and electrons are elementary particles that simultaneously exhibit particle and wave-type behavior.

Photons and electrons may appear to be quite different as described by classical physics, which defines photons as electromagnetic waves transporting energy and electrons as the fundamental charged particle (lowest mass) of matter.

A quantum description, on the other hand, reveals that

photons and electrons can be treated analogously and

exhibit many similar characteristics.

Let Let ’ ’ s warm s warm - - up up

일반물리 일반물리

전자기학 전자기학

Question 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

Secondary on-going wave

Primary incident wave

What about –r direction?

Electromagnetic Waves Electromagnetic Waves

ε0

A Q d E⋅ =

∫

= 0

∫

dt s d

d

E⋅ = − Φ^B

∫

dt i d

s d

B Φ^E

μ ε + μ

=

∫ ^G⋅ ^{G 0 0 0}

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

∫

∫

∫ ^{E⋅dA = ∇⋅Edv =} _ε^{ρ dv}

0

G G G

G

= 0

⋅

∇

=

⋅ ∫

∫ ^{BG dAG G BGdv}

∫

∫

∫ ^{⋅ = ∇× ⋅ = − B⋅dA}

dt A d

d E s

d

EG G G G G G G

∫

∫

∫

∫

⋅ ε

μ +

⋅ μ

=

ε Φ μ + μ

=

⋅

×

∇

=

⋅

A d dt E

A d d j

dt i d

A d B s

d

B ^E

G G G G

G G G G

G

0 0 0

0 0 0

t j E

B ∂

ε ∂ μ + μ

=

×

∇

G G G

G

0 0 0

jd

t

EG G

∂ =

ε₀ ∂ G BG

(

)

+ μ

=

×

∇ ₀

ε0

= ρ

⋅

∇ EG G

⇒

= 0

⋅

∇ BG G

⇒

t E B

∂

− ∂

=

×

∇ G G

⇒ G

⇒

⇒

Wave equations Wave equations

t E B

∂

− ∂

=

×

∇ G G G

t B E

∂

= ∂

×

∇ G G G

0 0ε μ

( )

⎠

⎜⎜ ⎞

⎝

⎛

∂

− ∂

∂

= ∂

×

∂ ∇

= ∂

×

∇

×

∇ t

B E t

B t

G G G G

G G

0 0 0

0ε μ ε

μ

(

)

G × ∇× = −∇2

∇ ^{x iˆ y ˆj ∂z kˆ}

+ ∂

∂ + ∂

∂

= ∂

∇G

(^{G BG}) ( )^{G G BG BG BG}

G × ∇× = ∇ ∇⋅ −∇2 = −∇2

∇

(^{B C}) ( ) ( )^{A C B A B C}

AG G G G G G G G G

⋅

−

⋅

=

×

×

2 2 0 0 2

t B B

∂

= ∂

∇ G G

ε μ

2 2 0 0 2

t E E

∂

= ∂

∇ G G

ε μ

2 0

2 0 2 0

2 =

∂

− ∂

∂

∂

t B x

B μ ε

2 0

2 0 2 0

2 =

∂

− ∂

∂

∂

t E x

E μ ε

Wave equations In vacuum

Scalar wave equation Scalar wave equation

2 2

0 0

2 2 0

x μ ε t

∂ Ψ − ∂ Ψ =

∂ ∂

0 cos(kx ωt)

Ψ = Ψ −

2 0

0 0

2 −μ ε ω =

k v c

k = = ≡

0 0

1 ε μ

ω Speed of Light

s m m

c = 2.99792×10⁸ /sec ≈ 3×10⁸ /

Transverse Electro

Transverse Electro--Magnetic (TEM) wavesMagnetic (TEM) waves

B t E

B EG G G

G

G ⇒ ⊥

∂ ε ∂ μ

−

=

×

∇ _{0 0}

Electromagnetic Wave

Energy carried by Electromagnetic Waves Energy carried by Electromagnetic Waves

Poynting Vector : Intensity of an electromagnetic wave

B E SG G G

×

=

0

1 μ

2 0 2

0 0

1 1

c B c E

EB S

= μ

= μ

= μ

(Watt/m²)

⎟⎠

⎜ ⎞

⎝⎛ = c E B

2

2 0

1 E u_E = ε

Energy density associated with an Electric field :

2

2 0

1 B u_B

= μ

Energy density associated with a Magnetic field :

n₁ n₂

Reflection and Refraction

1 1 = θ′

θ

Reflected ray

Refracted ray n₁sinθ₁ = n₂ sinθ₂

Smooth surface Rough surface

Reflection and Refraction

0 0

) ( )

) (

( μ ε

λ με λ = λ =

v n c

In dielectric media,

(Material) Dispersion

Interference & Diffraction

Reflection and Interference in Thin Films Reflection and Interference in Thin Films

• 180 º Phase change of the reflected light by a media

with a larger n

• No Phase change of the reflected light by a media

with a smaller n

Interference in Thin Films

t n₁

Phase change: π

n₂ Phase change: π

n₂ > n₁

λ

= λ

=

= δ

1

2 1

n m m

t _n

Bright ( m = 1, 2, 3, ···)

( ⁺ )^{λ = ( + )λ}

=

= δ

1 2 1 2

1

2 1

n m m

t _n

Bright ( m = 0, 1, 2, 3, ···) n t

Phase change: π

No Phase change

( ⁺ )^{λ = ( + )λ}

=

=

δ n

m m

t _n ²

1 2

2 1

λ

= λ

=

=

δ n

m m

t _n

2

Bright ( m = 0, 1, 2, 3, ···)

Dark ( m = 1, 2, 3, ···)

Interference

Young’s Double-Slit Experiment

Interference

The path difference

λ

= θ

=

δ d sin m

( ⁺ )^λ

= θ

=

δ d sin m ₂¹

⇒ Bright fringes m = 0, 1, 2, ····

⇒ Dark fringes m = 0, 1, 2, ····

The phase difference

λ θ

= π π λ ⋅

= δ

φ 2 d sin

2

θ

=

−

=

δ r₂ r₁ d sin

Hecht, Optics, Chapter 10

Diffraction

Diffraction

Diffraction Grating Grating

Diffraction of X

Diffraction of X - - rays by Crystals rays by Crystals

d θ θ

θ

dsinθ Incident

beam

Reflected beam

λ θ m d sin =

2 : Bragg’s Law

Regimes of Optical Diffraction Regimes of Optical Diffraction

d << λ d ~ λ

d >> λ

Far-field Fraunhofer

Near-field Fresnel

Evanescent-field Vector diff.

d <<

d << λ λ : : Nano Nano - - photonics photonics

d << λ

Science, Vol. 297, pp. 820-822, 2 August 2002.

Ag film, hole diameter=250nm, groove periodicity=500nm,

groove depth=60nm, film thickness=300nm

Ag film, slit width=40nm, groove periodicity=500nm,

groove depth=60nm, film thickness=300nm

Beaming light through a sub-wavelength hole

gold

Surface plasmons

42

Nano-scale focusing and guiding:

A single-photon transistor using nanoscale surface plasmons, Nature physics VOL 3 NOVEMBER 2007, pp.807-812.

E_r

E_z

E_r

Nanofocusing of Optical Energy in Tapered Plasmonic Waveguides, Phys. Rev. Lett. 93, 137404 (2004)]

Channel plasmon subwavelength waveguide components including interferometers and ring resonators, Nature, 440, 23 March (2006)]

Plasmonics: Merging photonics and electronics at nanoscale dimensions, Science, 311, 13 January (2006)]

Nano Photonic Lasers

Photonic crystal laser Photonic crystal laser

O. Painter et al, Science, 284, 1819-1821(1999)

Fiber coupling to PCL

- Barclay et al, Opt. Lett. 29, 697 (2004)

Nature physics VOL 3 NOVEMBER 2007, pp.807- 812.

Tapered SP coupling

PRL 97, 053002 (2006)

Single photon generation

Nano-scale photon measurement

S.-K. Eah et al., Appl. Phys. Lett. 86,031902 (2005)

Single gold nanoparticle interferometer

www.nanonics.co.il

NSOM & AFM

Nanophotonics

Nanophotonics for Bio for Bio - - Sensing Sensing

Analog M-WGPD

실리콘 기판

Sensing area (Cr 10nm, Au 50nm)

Analog WGPD

LD (TM polarized)

폴리머 or 실리카 도파로

S ilve r n a n o p article A n a lyte S ilver c o llo id

A n a lyte

La ser &

d etectio n p o int

S ilver n an o c lu ste rs

SERS & 대장균

NPIC chip

Nano 구조물

46

Fiber coupler

Nano plasmonic delay line

Plasmonic photodetector

Plasmonic splitter

Plasmonic switch Plasmonic coupler

Plasmonic crystal bends

Plasmonic

Plasmonic enhancedenhanced integrated chip integrated chip

A future of Nanophotonics; IBM, Purdue

47

Silicon Modulator

Plasmonic Crystals

Optical MEMS Devices

Chip-Chip

Plasmonic Interconnection Plasmonic Bio-Sensors

RF-Photonic Devices

Photonic Network

Intra-Chip Nano plasmonic Interconnection

A future of Nanophotonics; OPERA ERC

첨단 첨단 과학기술을 과학기술을 이끄는 이끄는 광학 광학

Nanophotonics