MICHELSON AND WHITE LIGHT INTERFEROMETRY

INTERFEROMETER TO MEASURE DISPERSION

Michelson Interferometer response

Michelson Interferometer response If beam 2 traverses L = 2d of glass instead of air, the field E2 is modified:

Michelson Interferometer response: shift in “time origin”

Michelson Interferometer: demonstration of a delayed response

Michelson Interferometer: sample testing Without sample: With sample: sample Ratio:

Michelson Interferometer: sample testing Do we need short pulses? Can we test mirrors? We are measuring directly k(W) to all orders (except zero and one)

Michelson Interferometer: sample testing sample White light = random sequence of ultrashort pulses

Interferogram without sample, and its Fourier Transform

Interferogram with 0.5 mm of fused silica in arm 2.

Interferogram for 2 mm of glass, spectrum and spectral phase. 30 60 90 120 -1.0 -0.5 0.0 0.5 1.0 Normalized Intensity (a.u.) Relative Delay ( m m) 100 200 300 400 Relative Delay (fs) m) m Wavelength ( 1.2 1 0.8 0.6 5 1.0 Spectrum Phase 0.8 Polynomial Fit -5 Spectral Amplitude (a.u.) 0.6 Spectral Phase (rad) -10 0.4 -15 0.2 -20 0.0 -0.5 0.0 0.5 1.0 W (1/fs)

Interferogram, spectrum and spectral phase. Mirror testing: Interferogram, spectrum and spectral phase. Relative Delay (fs) 0.0 0.5 1.0 Spectral Phase (rad) -0.4 -0.2 0.2 0.4 0.6 W (1/fs) i. 1.5 ii. 1 0.9 0.8 0.7 Wavelength ( m m) 100 200 300 1 b. Normalized Intensity (a.u.) -1 20 40 60 80 100 Relative Delay ( m m)