Kansas Light SourceLaser System

J. R. Macdonald LaboratoryDepartment of Physics, Kansas State University

September, 2010

Kansas Light Source: Amplified Ti:Sapphire Laser System

Noncolinear f-2f interferometer

Beam splitter

Chirp mirror compressore

Ne gas filled hollow fiber(L=1 m)

TiS crystal

Beam splitter

Stretcher

Spectrometer

FROG

Power meter

Colinear f-2f interferometer

Pump laser

Feedback loop to stabilize CEP

Ti:sapphire oscillator

Compressor

Pump laser

Amplifier

Mode-LockedTi:Sapphire Oscillator

350 mW Average Power12 fs Pulse Width

80 MHz Repetition Rate5 nJ Pulse Energy800 nm Central

Wavelength95 nm Bandwidth

Multi-passTi:Sapphire Amplifier4 W Average Power27 fs Pulse Width

2 KHz Repetition Rate2 mJ Pulse Energy780 nm Central

Wavelength40 nm Bandwidth

KLS output

Light Amplification by Stimulated Emission of Radiation

Light Amplification by Stimulated Emission of Radiation

Cavity mirror Cavity mirror/output coupler

Pump

Laser medium Laser output

Optical cavity→ LASER

Interaction of light with matterIn laser medium

Population inversion → LASER

AbsorptionSpontaneous

emissionStimulatedemission

Ti:Sapphire crystalTi3+:Al2O3

Chirped Pulse Amplification

Mode-locked oscillator

M6

M3

M0M1

Ti:SM5

M7

M4E M4

M2 M8CP

Note:M7, M8, M12 and M13 mirrors are chirped mirrors.M-1,M9 and M10 are periscopes. A 50% beam splitter in M9.

Lens

M-1

Horizontal polarization from oscillator

M9 M10

M11M12

M13

Power meter and spectrometer

Pump verdi

To stretcher and amplifier

To f to 2f system

OC

KLS oscillator -- FemtoLaser

CPA stretcher/compressor

PositiveDispersion

NegativeDispersion

KLS stretcher

KLS Multi-Pass Amplifier

KLS Multi-Pass Amplifier

FROG: Beam Diagnostic

spectrometer

BS

TranslationStage

M1

M2

M3

M4

M5

M6

BBO

From Laser

InfraredFilter

1k

2k

I1(t) I2(t)

KLS system

Oscillator PC1

PD1

CEP Control

Menlo System

Delay Generator

SRS 645

80 MHz

Pump1

Pump2

PC1

PC2

PC2

PD2 PD3 PD4

Oscilloscope

2 kHz

KLS system timing

Oscillator: pump laser, crystal chiller, photo diode, Menlo timing controller

Amplifier: crystal chamber and vacuum pump, liquid nitrogen controller, Dewar, delay generator, pockels cells, pockels cell power supplies, pump lasers, pump laser power supplies, pump laser control computers, pump laser chillers, photo diodes, oscilloscope, power meter, power monitor, power locking PID (proportional–integral–derivative) controller, spectrometer, spectrometer computer

FROG: spectrometer, spectrometer computer, CCD camera, FROG computer

Other: power meters, mobile spectrometer, IR viewer, IR cards

KLS subsystems and devices

Coated Mirrors (metal or dielectric): reflectivity, phase, bandwidth, damage thresholdBeamsplitters: dielectric coating, reflectivity and transmission, phase, bandwidth, damage thresholdLens and windows: coating, material, thicknessWave plates: coating, material, thicknessPolarizerChirped mirror and compensation platesGratings and prismsNonlinear optical crystals

Optics

SafetyWear your goggles

Know where the beam goesDo not put your eyes at the beam height

ContactKun Zhao (Harry)

Baozhen ZhaoAl Rankin

Well, let’s see some real stuff now

Spectrum, Dispersion, Chromatic Aberration

Chromatic and Astigmatism AberrationsOf a Lens

Birefringence and Wave Plate

Half-wave plate

Polarization, s or p

Energy, Power, Spectrum

Femtolaser oscillator

Horizontal

To f-2f system

Half wave plate

Pokcel cellPolarizer

Polarizer

Photodiode

Photodiode Flip Half wave plate

Fara

Polarizer

PolarizerHalf wave plate

Horizontal

Linear Horizontal+45degree

HorizontalTo amplifier

M9

M10IRIS1

IRIS2IRIS3

IRIS4

Sm1

Sm2

Sg1Sg2

Sc1 Sc2

Sm3

Sm4

Powermeter

Pump1

First pass

Second pass

Third pass

Fourth pass

Fifth pass

Sixth pass

Seventh pass

Photodiode1

Photodiode3-7

Photodiode2

Pump2

CCD

Photodiode14

Monitor Power meter

M1

M2

M3

M4

M5M6

M7

M10 M9

M8

M11

M12

M13

CEP Lock

Verdi-6

Femtolaser oscillator

Evolution 30 Evolution 30

PC1

PC2

Final Output

Stretcher

Compressor

Amplifier

Seed

Pump Pump

2

2

2

2

Oscillator PC1

PD1 CE measure

CE ControlMenlo System

Channel Timer

BNC 555B

System TimerBNC 555A

Pulse GeneratorPhilips PM5712

75 MHz, 1V

f/16

2V

f/45

A

B

C

D

f/4

Pump1380

Pump2302

PC11900

PC21940

10ns

5µs

PC2

PD275M-1kHz

400 mV

PD31 kHz

150 mV

PD41 kHz, 1V1.5 V, jitter 1 ns

to ExperimentOscilloscopeTek TDS3054

KLS Timing Jan 15, 2005

DG535 Pump1: A: 510 ns; B: A + 5 s Pump2: C: 310 ns; D: C + 5 sDelay Unit: > 1 usPC1: Delay 55 ns; Width 10 nsPC2: Delay 45 ns; Width 10 ns

DG535 0 AB CD

Pump1 Pump2

Delay OUT IN

Laser Metrics 5046INPUT

Q-SW CW

Trig Delay Width MON Outputs

HV Bias

HV Adj

Laser Metrics 5046INPUT

Q-SW CW

Trig Delay Width MON Outputs

HV Bias

HV Adj

Pockels Cell 1

Pockels Cell 2

Photo Diode

Long cable delay goes to control room

7.5 kV 7.5 kV

Master kHz signal is generated by DG535. PC1 is trigged by the kHz laser signal selected by the master signal and the signal from the photo diode. PC2 is trigged by the MON signal from PC1. Long cables are used for PC1 to compensate the trig delay of PC2

76 MHz kHz