Fig. 2: Real-time tracking of multiple levitated particles.
From: Neuromorphic detection and cooling of microparticles in arrays
a Reconstructed 2D position of four levitated microparticles tracked in real-time at a 1 kHz framerate. The amplitude of motion depends on the charge of each particle and where it sits within the levitating potential. Particles 2 and 4 are closest to and furthest from the Paul trap centre (the centre of the coordinate axes), respectively. b Position power spectral densities (PSDs) reconstructed from the 2D position tracking of the four particles in (a) (green trace: \({y}^{{\prime} }\)-direction, purple trace: \({z}^{{\prime} }\)-direction). Each particle is independently tracked. We observe interactions between particles in the array: \({x}_{{{{\rm{C}}}}}^{(1)}\), \({x}_{{{{\rm{C}}}}}^{(2)}\), \({x}_{{{{\rm{C}}}}}^{(3)}\) and \({x}_{{{{\rm{C}}}}}^{(4)}\) are four collective modes of all the four particles in the x-direction. We also see the individual bare modes in the y- and z-directions. For information on identifying modes, see Supplementary Materials S2 and S3.
