R. KiplingR. Kipling

…On absolutely

absurd,

definitely

impossible,

and unavailing.

Lasers, Coherent Light Lasers, Coherent Light and Modern Optical and Modern Optical

PhysicsPhysics(Basic Principles of Laser Applications)

What is laser

Most important features – coherent light

Concentration of electromagnetic radiation

Applications

The Wavelengths of Visible Radiation:  From 700 nm (7 ·10 -5 cm, red light) to 400 nm (4 ·10 -5 cm, violet). Optical Electro-Magnetic Radiation:(sub-millimeter) 10 -3 cm 10 -8 cm (x-rays). The speed of light in a vacuum is a fundamental physical constant c=299,792,458 metres per second, or about 186,282 miles per second (299,792 kilometres per second).

Visible range

Incoherent LightIncoherent Light

  

(a)and (b) –EM waves emitted by the different atoms at a fixed instant of time,

(c) – oscillation of electrical field at a fixed point (partially coherent radiation).

Coherent LightCoherent Light

Coherent oscillation of the strength of electrical field at a fixed point for t > t0 and t > t0+ .

T is period of oscillations.

It is a source of coherent, super-high-frequency EM

radiation which can be concentrated in:

spectral interval / ~ 10-15 (monochromatic);

solid angle (directed radiation) ~(/D)2 ~ 10-15;

spot A ~ ()2 and volume V ~()3 ~ 10-15 cm 3 (focusing);

time interval ~ 2/ ~ 10-15 s

E (I)1/2 = (Q/A)1/2

WHAT IS UNIQUE ABOUT LASERS?WHAT IS UNIQUE ABOUT LASERS?

precision measurements, instruments, selective resonant effects on atoms and molecules ( / ~ 10-15 , ~ 10-15 );

information capacity ( opt rad = rad opt ~ 50 m 500 nm = 10 8 , 10 8 s = 1,157 · 24 hrs 3.17 years; DWDM – dense wave division multiplexing, 10 … 100 Gb/s; V ~()3 ~ 10-15 cm 3 10 15 bytes/cm3 ~ 1 million Gb /cm3 );

electric and magnetic fields of super-high intensity ( I = Q/A 1,000J/ 10-15 s 10 -10 cm 2 = 10 28 W/cm 2 ,

E ( I ) 1/2 , I = 10 16 W/cm 2 E 5 ·10 9 V/cm = Eat . Er/Eor ~ /, Ir/Ior ~ ( /)2 ~ 10 -16 . )

Fundamentals of laser Fundamentals of laser applicationsapplications

•BIOLOGY, MEDICINE, PHOTOCHEMISTRY

•ISOTOPE SEPARATION, THERMO-NUCLEAR FUSION

•OPTO-ELECTRONICS, INTEGRATED OPTICS

•OPTICAL MEMORY AND DATA STORAGE (RAM and ROM)

•ALL-OPTICAL AND QUANTUM COMPUTERS •ADAPTIVE OPTICS and WAVE–FRONT CONJUGATION •OPTICAL (FIBEROPTICAL) NETWORKING

•RANGE-FINDING, LIDARS, REMOTE SENSING

•MATERIAL PROCESSING, MICRO&NANO TECHNOLOGIES

LASER APPLICATIONSLASER APPLICATIONS

E(t, z) = j Aj cos(j t – kj z),

E = ½ j [Aj exp(ij t + kj z) + k.c.].

P (L) (t, z) = (1)· E (t, z), P = P (L) + P (NL) .

P (NL) (t, z) = (1) · E (t, z) + (2) · E2 (t, z) + (3) · E3 (t, z) + …= (E) · E.

cos2x = ½(1 + cos 2x), cos3x = ¼ (3cos x + cos 3x).

Formula PNL...

Y.R. Shen. Principles of Nonlinear Y.R. Shen. Principles of Nonlinear Optics.Optics.

Physics would be dull and life most unfulfilling if all physical phenomena around us were linear. Fortunately, we are living in nonlinear world. While linearization beautifies physics, nonlinearly provides excitement in physics.

Harmonics Generation,Frequency-mixing,

Wave-surface Correction,Image Restoration

Nonlinear Absorption

Nonlinear Refraction

Multi-photonAbsorption,

Emission, andSpectroscopy

Self-focusing Self-defocusing,

Self-action

Coherent Processes Incoherent Processes

Nonlinear Optics: Nonlinear Optics: subdivisionssubdivisions

Very diverse and contradictious gossips have been circulating about those territories cut from the world and administrative influence.

Arkady and Boris Strugatsky

yy = = a sin ( kz - a sin ( kz - t),t), yy22 = a sin (kz= a sin (kz++t), y =t), y = yy11++yy2 2 = (= (2a 2a sin kzsin kz ) cos () cos (t)t)

Fig 1. (Standing wave)

P(t) = Nd(t)

P(t) = L Ep (t) + (3) E(t) 2 Ep(t)

InterferenceInterference

Fig 1. Energy levels and coupled Fig 1. Energy levels and coupled fieldsfields

NaNa2 2 : X’: X’gg++(v’’ = 0, J’’ = 45) - A’ (v’’ = 0, J’’ = 45) - A’

u u ++(6,45) ((6,45) (1 1 = = 655655 nm) - nm) -

X’X’gg+(14,45) (+(14,45) (2 2 ==756756 nm) - nm) -

B’B’ u u (5,45) ((5,45) (3 3 = = 532532 nm) - nm) -

X’X’gg++(0,45) ((0,45) (4 4 = 480 nm)= 480 nm)

44 + + 22 = = 11 + + 33

Fantasies require details.  

M. Svetlov

GG1010=60MH=60MHzz

G30=20MHz

L4= 40-1

Maxwell’s DemonMaxwell’s Demon

Maxwell’s Demon

E. RutherfordE. Rutherford

I think all that is very simple.

http://search.britannica.com/search?adv

Optics, light, electromagnetic radiation.

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