Ian Walmsley

Abstract:

We show that frequency-resolved optical gating combined with spectral interferometry yields an extremely sensitive and general method for temporal characterization of nearly arbitrarily weak ultrashort pulses even when the reference pulses is not transform limited. We experimentally demonstrate measurement of the full time-dependent intensity and phase of a train of pulses with an average energy of 42 zeptojoules (42 x 10(-21) J), or less than one photon per pulse.

Abstract:

An electro-optic phase modulator in a regenerative mode-locker configuration is demonstrated as the starting mechanism for a Kerr-lens mode-locked Ti:sapphire laser. Mode locking is initiated automatically, and the system is capable of pulses as short as 21 fs.

Abstract:

We formulate the first-order properties of a general two-beam interferometer. We show that it may be completely described by the light source position and the location, orientation, and size of the two images of this light source as seen from the observation plane, plus the image-plane position and the location, orientation, and size of the two images of this observation screen as seen from the light source position, plus the optical path difference between the two possible optical paths. The parameters are quite similar to those previously defined by Steel [W. H. Steel, Interferometry, 2nd ed. (Cambridge U. Press, New York, 1983)].