  The study of quantum resonances in the chaotic atom-optics kicked rotor
system is of interest from two different perspectives. In quantum chaos, it
marks out the regime of resonant quantum dynamics in which the atomic cloud
displays ballistic mean energy growth due to coherent momentum transfer.
Secondly, the sharp quantum resonance peaks are useful in the context of
measurement of Talbot time, one of the parameter that helps in precise
measurement of fine structure constant. Most of the earlier works rely on
fidelity based approach and have proposed Talbot time measurement through
experimental determination of the momentum space probability density of the
periodically kicked atomic cloud. Fidelity approach has the disadvantage that
phase reversed kicks need to be imparted as well which potentially leads to
dephasing. In contrast to this, in this work, it is theoretically shown that,
without manipulating the kick sequences, the quantum resonances through
position space density can be measured more accurately and is experimentally
feasible as well.
