Rotational dynamics of a diatomic molecular ion in a Paul trap

Abstract

We present models for a heteronuclear diatomic molecular ion in a linear Paul trap in a rigidrotor approximation, one purely classical and the other where the center-of-mass motion is treated classically, while rotational motion is quantized. We study the rotational dynamics and their influence on the motion of the center-of-mass, in the presence of the coupling between the permanent dipole moment of the ion and the trapping electric field. We show that the presence of the permanent dipole moment affects the trajectory of the ion and that it departs from the Mathieu equation solution found for atomic ions. For the case of quantum rotations, we also evidence the effect of the above-mentioned coupling on the rotational states of the ion. C 2015 AIP Publishing LLC. [http://dx

Quantum stability of an ion in a Paul trap revisited

“…Such a conclusion is also supported by other theoretical derivations [20][21][22] and numerical simulations of the wave-packet dynamics [23]. While these studies pertain to atomic ions, non-polar molecules have the same centre-of-mass trajectories as atomic ions, and we have also recently shown that the interaction between the trapping field and a dipole moment doesn't lead to a noticeable modification of the stability criterion [24].…”

Electric trapping and circuit cooling of charged nanorotors

“…We derived the effective trapping potential for aspherical objects with non-vanishing permanent electric multipole moments in quadrupole ion traps, and numerically demonstrated cooling in a realistic setup. The derived relations will be relevant for quantum experiments with charged molecules and nanoparticles [27,33,[38][39][40]68].…”

“…The endcaps are held at a voltage of U ec with respect to ground. This trap geometry was used for instance in the experiments reported in [38,39,68].…”

“…Also all-electric schemes are feasible, given that purely electric cooling and manipulation techniques devised for atomic ions [37] can be applied to charged objects of arbitrary shape and size. However, the particle dynamics are then determined not only by the electric monopole, but depend also on higher multipole moments, which couple the rotational and translational particle motion to the time-dependent trapping and manipulation fields [27,[38][39][40].…”

Thermodynamic properties of the trigonometric Rosen-Morse potential and applications to a quantum gas of mesons

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