A polyphonic acoustic vortex and its complementary chords

作者:Wilson C*; Padgett M J
来源:New Journal of Physics, 2010, 12: 023018.
DOI:10.1088/1367-2630/12/2/023018

摘要

Using an annular phased array of eight loudspeakers, we generate sound beams that simultaneously contain phase singularities at a number of different frequencies. These frequencies correspond to different musical notes and the singularities can be set to overlap along the beam axis, creating a polyphonic acoustic vortex. Perturbing the drive amplitudes of the speakers means that the singularities no longer overlap, each note being nulled at a slightly different lateral position, where the volume of the other notes is now nonzero. The remaining notes form a tri-note chord. We contrast this acoustic phenomenon to the optical case where the perturbation of a white light vortex leads to a spectral spatial distribution.

  • 出版日期2010-2-15