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Jonathan R Birge

Publications and source records attributed to Jonathan R Birge.

3 recordsLinked to original sources

Two-dimensional spectral shearing interferometry for few-cycle pulse characterization.

We present a new method for measuring the spectral phase of ultrashort pulses that utilizes spectral shearing interferometry with zero delay. Unlike conventional spectral phase interferometry for direct electric-field reconstruction, which encodes phase as a sensitively calibrated fringe in the spectral domain, two-dimensional spectral shearing interferometry robustly encodes phase along a second dimension. This greatly reduces demands on the spectrometer and allows for complex phase spectra to be measured over extremely large bandwidths, potentially exceeding 1.5 octaves.

Journal Article↗

Efficient analytic computation of dispersion from multilayer structures.

We demonstrate an inductive method for computing exact derivatives of reflection phase for layered media by using the transfer-matrix formalism. The algorithm scales linearly with the number of layers. We show a physically realistic approximation that leads to an efficient procedure for accurately computing dispersion significantly faster than with standard finite-difference methods. We discuss the theory behind the approximation and show results for a dispersion-compensating chirped mirror from a Ti: sapphire laser.

Journal Article↗

Ultrabroadband beam splitter with matched group-delay dispersion.

We present a general design strategy for a broadband thin-film beam splitter with matched group-delay dispersion. By taking the substrate dispersion into account in the coating design, any combination of input and output can show the same dispersion for transmission and reflection. As a specific implementation, an ultrabroadband 50:50 beam splitter from 600 to 1500 nm for femtosecond laser applications was designed, fabricated, and characterized.

Journal Article↗