  We present the results of a search for pulsed very-high-energy (VHE)
gamma-ray emission from young pulsars using data taken with the H.E.S.S.
imaging atmospheric Cherenkov telescope system. Data on eleven pulsars,
selected according to their spin-down luminosity relative to distance, are
searched for gamma-ray signals with periodicity at the respective pulsar spin
period. Special analysis efforts were made to improve the sensitivity in the
100 GeV gamma-ray energy domain in an attempt to reduce the gap between
satellite and ground-based gamma-ray instruments. No significant evidence for
pulsed emission is found in any data set. Differential upper limits on pulsed
energy flux are determined for all selected pulsars in the approximate
gamma-ray energy range between 100 GeV and 50 TeV, using different limit
determination methods, testing a wide range of possible pulsar light curves and
energy spectra. The limits derived here imply that the magnetospheric VHE
gamma-ray production efficiency in young pulsars is less than 10^-4 of the
pulsar spin-down luminosity, requiring spectral turnovers for the high-energy
emission of four established gamma-ray pulsars, and constrain the inverse
Compton radiation component predicted by several outer gap models.
