Single-Shot Detection of Wavepacket Evolution
Abstract
We have developed a detector for monitoring the time-dependent evolution of dynamic states in atoms using a single electromagnetic pulse pair. The detector utilizes pump and probe beams which cross through a sample of atoms. The pump pulse excites a wavepacket in each atom. The final state of the atom after the probe pulse depends on the evolution of the non-stationary state during the time interval between the two pulses. However, because the beams cross at a non-zero angle, the relative delay between the pump and probe pulses varies linearly across the interaction region. The spatial distribution of the ions formed directly by the probe or through subsequent photo- or field ionization is imaged using a phosphor screen and CCD camera. In this way, wavepacket evolution can be monitored over a range of times in a single shot. This detector greatly reduces the time required to make time-domain measurements using low repetition rate laser systems. The resolution of the detector is determined by the angle between the pump and the probe beams. We have achieved resolutions of <1 fsec in a nearly colinear geometry and <1 psec for counter-propagating beams using the same apparatus.
- Publication:
-
APS April Meeting Abstracts
- Pub Date:
- April 1997
- Bibcode:
- 1997APS..APR.D1559C