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arXiv · 2009.11755

Impulsively Excited Gravitational Quantum States: Echoes and Time-resolved Spectroscopy

I. Tutunnikov·K. V. Rajitha·A. Yu. Voronin·V. V. Nesvizhevsky·I. Sh. Averbukh
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Abstract

We theoretically study an impulsively excited quantum bouncer (QB) - a particle bouncing off a surface in the presence of gravity. A pair of time-delayed pulsed excitations is shown to induce a wave-packet echo effect - a partial rephasing of the QB wave function appearing at twice the delay between pulses. In addition, an appropriately chosen observable [here, the population of the ground gravitational quantum state (GQS)] recorded as a function of the delay is shown to contain the transition frequencies between the GQSs, their populations, and partial phase information about the wave packet quantum amplitudes. The wave-packet echo effect is a promising candidate method for precision studies of GQSs of ultra-cold neutrons, atoms, and anti-atoms confined in closed gravitational traps.

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BibTeXRIS

I. Tutunnikov, K. V. Rajitha, A. Yu. Voronin, V. V. Nesvizhevsky, I. Sh. Averbukh. 2020-09-24. Impulsively Excited Gravitational Quantum States: Echoes and Time-resolved Spectroscopy. https://doi.org/10.1103/physrevlett.126.170403

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