Effect of an echo sequence to a trapped single-atom interferometer with photon momentum kicks

Area of Science:

• Quantum optics
• Atomic physics
• Interferometry

Background:

• Single-atom interferometers (SAI) are sensitive quantum tools.
• Optical dipole traps (ODT) confine atoms for precise manipulation.
• Raman transitions are crucial for manipulating atomic states in interferometry.

Purpose of the Study:

• To investigate the decay mechanisms of interference visibility in ODT-guided SAIs.
• To compare the performance of counter-propagating versus co-propagating Raman pulses in SAIs.
• To understand the role of state-dependent dipole potentials in atomic wave-packet evolution.

Main Methods:

• Experimental realization of a single-atom interferometer within an optical dipole trap.
• Implementation of an echo sequence for enhanced interferometric measurements.
• Development of a wave-packet propagation simulation to model atom dynamics.

Main Results:

• Interference visibility decays significantly faster for counter-propagating Raman pulses compared to co-propagating ones.
• State-dependent dipole potentials couple external atomic motion with internal states, leading to path separation.
• Echo interference visibility exhibits revival or collapse dependent on the timing of applied π pulses relative to the trap period.

Conclusions:

• The rapid decay in counter-propagating SAIs is attributed to the forced separation of atomic wave packets.
• The interaction within state-dependent potentials is key to understanding decoherence in ODT-guided SAIs.
• Echo sequences reveal rich dynamics, including revival and collapse, offering insights into quantum control.