arXiv subjects

O. Lakhmanskaya

Publications and source records attributed to O. Lakhmanskaya.

3 recordsLinked to original sources

arXiv2026

Mølmer-Sørensen gates in trapped-ions chains in the presence of correlated noise

We analyze the impact of correlated laser frequency noise on Mølmer-Sørensen gates in qubit registers based on trapped-ion chains. Using perturbation theory, we calculate gate fidelities in the presence of noise with arbitrary power spectral density for different chain lengths and ion positions in the chain. With our approach, we account for simultaneous excitation of multiple phonon modes during gate operation. We find out that the impact of medium-frequency laser noise depends considerably on the positions of the ions in the chain. In contrast, low-frequency noise has similar effect for different chain lengths and ion positions.

quant-ph↗

arXiv2025

Towards practical non-Markovianity measures: Normalization and regularization techniques

Measures characterizing the non-Markovianity degree of the quantum dynamics have several drawbacks when applied to real devices. They depend on the chosen measurement time interval and are highly sensitive to experimental noise and errors. We propose several techniques to enhance the practical applicability of the measures and verify our findings experimentally on a superconducting transmon and a trapped-ion qubit. The time dependence can be disregarded by introduction of the measure per oscillation, while the sensitivity to noise is reduced by applying a regularization procedure. The results for both types of qubits are compared with theoretical predictions for a simple model of non-Markovianity based on qubit-qubit interaction.

quant-ph↗

arXiv2017

Incomplete rotational cooling in a 22-pole ion trap

Cryogenic 22-pole ion traps have found many applications in ion-molecule reaction kinetics and in high resolution molecular spectroscopy. For most of these applications it is important to know the translational and internal temperatures of the trapped ions. Here, we present detailed rotational state thermometry measurements over an extended temperature range for the two ion/buffer gas systems OH-/He and OD-/HD with ion-to-neutral mass ratios of 4.25 and 6 respectively. The measured rotational temperatures show a termination of the thermalisation with the buffer gas around 25K, independent of mass ratio and confinement potential of the trap. Different possible explanations for this incomplete thermalisation have been investigated, among them the thermalisation of the buffer gas and the heating due to room temperature blackbody radiation and room temperature gas entering the trap.

physics.atom-ph↗