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Translational effects on electronic and nuclear ring currents.

¹Max-Born-Institut, Max-Born-Strasse 2A, 12489 Berlin, Germany. barth@mbi-berlin.de

The Journal of Physical Chemistry. A

|August 11, 2012

Summary

This summary is machine-generated.

Electronic and nuclear ring currents in excited atomic and molecular systems decay much faster in the laboratory frame than previously thought. Translational wavepacket spreading significantly shortens the persistence of these quantum phenomena.

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Area of Science:

Quantum dynamics
Atomic and molecular physics
Laser-matter interactions

Background:

Previous predictions suggested long-lived electronic and nuclear ring currents in excited states after laser pulses.
These predictions were based on the center-of-mass frame, neglecting translational effects.

Purpose of the Study:

To investigate the influence of translational motion on ring currents in the laboratory frame.
To derive analytic formulas for ring current properties considering wavepacket widths.

Main Methods:

Theoretical derivation of analytic formulas for ring current densities, radii, and induced magnetic fields.
Analysis of the impact of translational wavepacket spreading on decay timescales.

Main Results:

Ring currents and magnetic fields decay on shorter timescales in the laboratory frame due to translational wavepacket spreading.
Electronic ring currents decay on femtosecond timescales.
Nuclear ring currents decay on zeptosecond timescales, exhibiting giant magnetic fields and small radii.

Conclusions:

Translational motion is crucial for accurately describing ring current dynamics in the laboratory frame.
Nuclear ring currents are transient phenomena decaying on extremely short timescales.