Trapped ions dynamics

The second method involved the application of a DC potential to the connected end-cap electrodes and varied adiabatically, that is, the DC potential was varied slowly such that the ion cloud was not disturbed by this variation. The variation of the fluorescence as a function of the adiabatically-varied DC voltage, in the absence of any other external excitation, reveals two important properties of trapped ion dynamics first, the boundaries of the stability diagram and, second, the intensity of possible black canyons (see Chapter 3 in Vol. 1 of this series). 

Here, we rq>ort related trapped-ion research at NIST on (1) the study of the dynamics of a two-level atomic system coupled to harmonic atomic motion, (2) the creation and characterization of nonclassical states of motion such as Schrodinger-cat superposition states, and (3) quantum logic for the generation of highly entangled states and for the investigation of scaling in a quantum computer. 

The key to making a quantum logic gate is to provide conditional dynamics that is, we desire to perform on one physical subsystem a unitary transformation which is conditioned upon the quantum state of another subsystem [46]. In the context of cavity QED, the required conditional dynamics at the quantum level has recently been demonstrated [50,51]. For trapped ions, conditional dynamics at the quantum level has been demonstrated in verifications of zero-point laser cooling where absorption on the red sideband depended on the motional quantum state of the ion [11,12]. Recently, we have demonstrated a CN logic gate in this experiment, we also had the ability to prepare arbitrary input states to the gate (the keyboard operation of step (2a) below). 

D. Leibfried, R. Blatt, C. Monroe, D. Wineland, Quantum dynamics of single trapped ions. 

Quadrupole ion traps ions are dynamically stored in a three-dimensional quadrupole ion storage device (Fig. 10.6) [37]. The RF and DC potentials can be scanned to eject successive mass-to-charge ratios from the trap into the detector (mass-selective ejection). Ions are formed within the ion trap or injected into an ion trap from an external source. The ions are dynamically trapped by the applied RF potentials (a common trap design also makes use of a bath gas to help contain the ions in the trap). The trapped ions can be manipulated by RF events to perform ion ejection, ion excitation, and mass-selective ejection. This provides MS/MS and MS experiments, which are eminently suited for structure determinations of biopolymers [38] (see Section 10.4). 

Structure and Dynamics of Trapped Ions (a) Diffraction (b) Background... 

James, D.F.V. Quantum dynamics of cold trapped ions with apphcation to quantum computation. AppZ. Phys. B. 1998, 66, 181-190. 

In the following section, the main properties of the linear ion trap and their effect upon the ion dynamics, particularly with respect to the potential distribution, will be described, followed by descriptions of some devices that have been realized. 

Aside from quadrupoles and ion traps, other dynamic analyzers [114] such as the monopoles have been merely of theoretical interest. 

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