Mesoscopic superpositions of distinguishable coherent states provide ananalog to the Schr\"odinger's cat thought experiment. For mechanicaloscillators these have primarily been realised using coherent wavepackets, forwhich the distinguishability arises due to the spatial separation of thesuperposed states. Here, we demonstrate superpositions composed of squeezedwavepackets, which we generate by applying an internal-state dependent force toa single trapped ion initialized in a squeezed vacuum state with 9 dB reductionin the quadrature variance. This allows us to characterise the initial squeezedwavepacket by monitoring the onset of spin-motion entanglement, and to verifythe evolution of the number states of the oscillator as a function of theduration of the force. In both cases, we observe clear differences betweendisplacements aligned with the squeezed and anti-squeezed axes. We observecoherent revivals when inverting the state-dependent force after separating thewavepackets by more than 19 times the ground-state root mean squared extent,which corresponds to 56 times the root mean squared extent of the squeezedwavepacket along the displacement direction. Aside from their fundamentalnature, these states may be useful for quantum metrology or quantum informationprocessing with continuous variables.
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