Single atom energy-conversion device with a quantum load
We report on a single atom energy-conversion quantum device operating as an engine, or a refrigerator, coupled to a quantum load. The “working fluid” consists of the two optical levels of an ion, while the load is one of its vibrational modes, cooled down to the quantum regime. We explore two important differences with classical engines: (i) the presence of a strong generic coupling interaction between engine and load which can induce correlations between them; (ii) the use of non-thermal baths. We examine the ergotropy of the load, which indicates the maximum amount of energy of the load extractable using solely unitary processes. We show that ergotropy rises with the number of engine cycles despite an increase in the entropy of the load. The increase of ergotropy of the load points to the possibility of using the phonon distribution of a single atom as a form of quantum battery.
A single atom noise probe operating beyond the Heisenberg limit
According to the Heisenberg uncertainty principle, the energy or frequency uncertainty of a measurement can be at the best inversely proportional to the observation time (TT). The observation time in an experiment using a quantum mechanical probe is ultimately limited by the coherence time of the probe....
Defect generation and dynamics during quenching in finite size homogeneous ion chains
An equally spaced linear chain of ions provides a test-bed for studying the defect formation in a finite size 1D system. In particular, defect formation related to topological phase transition from a linear configuration to a zig-zag one is of interest here. A semi-empirical expression provides an excellent agreement to the numerical results. The non-adiabatic transition between the chain and zig-zag topologies for a finite size system of 30 ions shows clear distinction from non-uniformly distributed ion chain. Thus the underlying Homogeneous Kibble-Zurek model can be tested in presently accessible ion trap experiments. Furthermore, our study indicates collective defect behaviour appearing through the correlation length measurements.
Tellurium has new reference lines
Phonon dynamics in ion traps
High resolution spectroscopy on Te2: New lines for reference
Optical Barium Ion Qubit
Magnetic coherent population trapping in a single ion
Squeezing Enhances Quantum Synchronization
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