490 MHz spaced optical frequency comb based on an Yb-fiber-ring laser

Peng Li, Aimin Wang and Zhigang ZhangSchool of Electronics Engineering and Computer

Science, Peking Universitypengli@pku.edu.cn

CLEO 2012 CTh1J.3

Outline

Introduction

Motivation

Challenge and Solutions

Experimental Schematic

Results and Discussions

Conclusions

Trend low phase noise

high repetition rate

high power

wide spectral coverage

great robustness

N.R.Newbury et al, Nature Photon. 5, 186–188(2011)

Introduction

• Solid state based

High repetition rate capability

Low noise

Lack long term stability

High cost

• Fiber based

Long term stability

High noise

Lack high repetition rate capability

Low cost

Methods

Motivation

Yb-fiber-ring laser

High efficiency

High power

High repetition rate capability

Short pulses generation mechanism

Goal

High repetition rate Yb-fiber-ring laser based optical frequency comb

Challenge and SolutionsChallenge

High repetition rate Yb-fiber-ring laser

Low power pumped octave-span-spectrum generatio

Solutions

Semi-WDM

Highly doped gain fiber

Tapered PCF

Experimental Schematic

PART 1

PART 2

PART 3

Experimental Schematic

Repetition rate: 490 MHz

Output power: 250 mW (800 mW pump)

Output spectrum bandwidth: 38nm

1.7 W, 77 fs

1 W

600 nm – 1300 nm

1 10 1001E-13

1E-12

1E-11

Alla

n D

evia

tio

n

Tau (s)

Allan Deviation

0 200 400 600 800 1000

-60

-40

-20

0

Inte

nsi

ty (

dB

)Frequence (MHz)

RF SpectrumSampled Frequency

0 1000 2000 3000 4000488149269.988

488149270.007

Fre

qu

ency

(H

z)Time (s)

950 1000 1050 1100 1150-90

-80

-70

-60

-50

Po

wer

(d

B)

Wavelength (nm)

Optical Spectrum

1000 1025 1050 1075 1100-80

-70

-60

-50

-40

Inte

nsi

ty (

dB

)

Wavelength (nm)

Optical Spectrum

-900 -600 -300 0 300 600 9000.0

0.2

0.4

0.6

0.8

1.0

Inte

nsi

ty (

a.u

.)

Time Delay (fs)

Autocorrelation

500 750 1000 1250 1500-70

-60

-50

-40

-30

Po

we

r (d

B)

Wavelength (nm)

632 nm 1264 nm

Results and Discussion

500 750 1000 1250 1500-70

-60

-50

-40

-30

Po

we

r (d

B)

Wavelength (nm)

632 nm 1264 nm

22 0 0

2

D

NL

PTLN

L

Soliton order in octave-span-spectrum generation

Un-tapperedTappere

d

T0 (fs) 77 77

P0 (kW) 26 26

β2 (fs2) 2.5 -102

γ (W-1km-1) 11 57

N 26 9

Results and DiscussionPump noise influence on fceo line width

0 1 2 3 4-0.6

-0.4

-0.2

0.0

0.2

0.4

0.6

Vo

ltag

e (V

)

Time (s)0 1 2 3 4

-0.6

-0.4

-0.2

0.0

0.2

0.4

0.6

Vo

ltag

e (V

)

Time (s)

0 100 200 300 400-50-45-40-35-30-25-20-15-10

Po

wer

(d

B)

Frequence (MHz)

RBW 300 kHz

0 100 200 300 400-50-45-40-35-30-25-20-15-10

Po

wer

(d

B)

Frequence (MHz)

RBW 300 kHz

Noisy Pump Silent Pump

PumpIntensity

fceo

Results and DiscussionDispersion influence on fceo line width

0 100 200 300 400-50

-40

-30

-20

-10

Po

wer

(d

B)

Frequency (MHz)0 100 200 300 400

-60

-50

-40

-30

-20

-10

Po

wer

(d

B)

Frequency (MHz)

950 1000 1050 1100 1150

-80

-70

-60

-50

-40

-30

Po

wer

(d

B)

Wavelength (nm)950 1000 1050 1100 1150

-90

-80

-70

-60

-50

Po

wer

(d

B)

Wavelength (nm)

RBW 300 kHz RBW 300 kHz

Spectrum

fceo

Soliton DM Soliton

Conclusions• 490 MHz NPE mode locked Yb-fiber-ring laser

• 1.7 W, 77 fs pulses pumping 600 nm – 1300 nm spectrum

• 33 dB S/N fceo at 100 kHz RBW

• fceo stabilization will be done

400 450 500 550 600-70

-60

-50

-40

-30

-20

-10

Inte

nsi

ty (

dB

)

Frequency (Mhz)

33dB

RBW 100 kHz

Thank you