Time lens

Zhengran L.B.R

Tuesday, April 23, 2013

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Outline

Origin

Realization

Application

Progress

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lens

Time lens

spatial

temporal

Origin

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Space-Time Duality

time lens:quadratic phase modulation

“Space-Time Duality and the Theory of Temporal Imaging” JOQE,1994

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Temporal-imaging Vs. Spatial-imaging

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Temporal-imaging condition

①

② ③

④①

②

③

④

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Temporal-imaging condition

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Temporal-imaging condition

Temporal-imaging condition Spatial-imaging condition

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EO PM

FWM/S/D-F/XPM

Using second-order nonlinearity material

Using any material including silica glass and silicaElectro-optical phase modulator

Realization

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Pulse compression

Time magnification

Real-time Fourier transformers(Time-to-frequency conversion)

Temporal cloaking

Optical Sampling

Tunable delay

Timing-jitter reduction

Application

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“Silicon-chip-based ultrafast optical oscilloscope”nature,2008

220-fs resolution

Time-to-frequency conversion using a single

time lensJose Azana

Photonic Systems Group, Department of Electrical and Computer Engineering, McGill University, 3480University Street,

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Dispersion-time lens dualism

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Analysis- First-order dispersion

A dispersive medium can be described as a phase-only filter with a frequency transfer function:

First-order dispersion coefficient of the medium:

temporal impulse response:

Filter impulse response:

Fourier transforms of b(t):

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Analysis-time lens

a time lens is a phase-only modulator with a modulation function:

Modulated signal:

Fourier transform of the time-lens modulation function m(t):

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Dual Fraunhofer regimes

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Frequency-to-time conversion

If the dispersion coefficient verifies the condition(temporal Fraunhofer condition):

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Time-to-frequency conversion

If this bandwidth is sufficiently narrow so that:

Can be neglected

So:

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Numerical simulations

FWHM:1psΔT: 5ps

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Simulation results

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Spectrum analyzer

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“Optical time lens based on four-wave mixing on a silicon chip” OL,2008

290ps

Progress

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“Asynchronous Single -Shot Optical Sampling of High -Repetition-Rate Signals Using Temporal Magnification” OFC 2013

11GHz

225GHz

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Demonstration of temporal cloaking,nature,2012

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Thank you!