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arXiv · 1505.07318

Direct Measurement of Time-Frequency Analogues of Sub-Planck Structures

Ludmila Praxmeyer·Chih-Cheng Chen·Popo Yang·Shang-Da Yang·Ray-Kuang Lee
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Abstract

Exploiting the correspondence between Wigner distribution function and a frequency-resolved optical gating (FROG) measurement, we experimentally demonstrate existence of the chessboard-like interference patterns with a time-bandwidth product smaller than that of a transform-limited pulse in the phase space representation of compass states. Using superpositions of four electric pulses as realization of compass states, we have shown via direct measurements that displacements leading to orthogonal states can be smaller than limits set by uncertainty relations. In the experiment we observe an exactly chronocyclic correspondence to the sub-Planck structure in the interference pattern appearing for superposition of two Schödinger-cat-like states in a position-momentum phase space.

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Ludmila Praxmeyer, Chih-Cheng Chen, Popo Yang, Shang-Da Yang, Ray-Kuang Lee. 2015-05-27. Direct Measurement of Time-Frequency Analogues of Sub-Planck Structures. https://doi.org/10.1103/physreva.93.053835

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