Quantum control of the motional states of trapped ions through fast switching of trapping potentials

Abstract

We propose a new scheme for supplying voltages to the electrodes of microfabricated ion traps, enabling access to a regime in which changes to the trapping potential are made on timescales much shorter than the period of the secular oscillation frequencies of the trapped ions. This opens up possibilities for speeding up the transport of ions in segmented ion traps and also provides access to control of multiple ions in a string faster than the Coulomb interaction between them. We perform a theoretical study of ion transport using these methods in a surface-electrode trap, characterizing the precision required for a number of important control parameters. We also consider the possibilities and limitations for generating motional state squeezing using these techniques, which could be used as a basis for the investigation of Gaussian-state entanglement.

Fast shuttling of a trapped ion in the presence of noise

“…Envisaged experiments at shuttle times of the order of an oscillation period [30] require changes of the trapping potential on time scales much shorter than the period corresponding to the trap frequency. At such fast temporal changes of the control voltages, the cutoff frequency for noise filtering elements must be very high, and thus we expect that it might be increasingly difficult to reach a low noise level.…”

“…The corresponding G(T ; n) is Bang-bang protocol. Finally let us examine the simple bang-bang protocol [30]:…”

Energy consumption for ion-transport in a segmented Paul trap

“…Filters are preferably placed close to the trap electrodes, inside the vacuum chamber housing the trap. In this way, it is possible to suppress significantly the amplitude of noise generated at the voltage supplies or picked up along the wires connecting these to the trap electrodes [27]. The filters are commonly built with a resistor R and capacitor C (first-order RC filters), although higher order filters and active filters are also possible.…”

Rotational dynamics of a diatomic molecular ion in a Paul trap

“…[10][11][12][13][14][15] One of the most applied techniques to trap these cold ions is known as the Paul trap, using time-dependent radiofrequency electric fields. 16 Paul traps, specifically those with a linear configuration, 17 consist of electrodes designed to surround an inner space where the trapping of a single charged particle, as well as the simultaneous trapping a string of charged particles, occurs.…”