Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Journal of Physics B Atomic Molecular and Optical Physics

Half-cycle microwave ionization of Rydberg atoms: beyond diabatic ionization

Philip Trøst Kristensen, G. M. Lankhuijzen, Lambertus D. Noordam

Published Mar 28, 1997• 16 citations
Publisher

Abstract

Ionization of Rydberg atoms by short, half-cycle electrical pulses is investigated experimentally in the intermediate-pulse duration regime where the ionization threshold fields are determined both by the slew rate of the ionizing pulse and its duration. Electrical pulses with durations ranging from 140 ps to 9 ns and amplitudes up to are applied to rubidium and lithium atoms prepared in high Rydberg states by laser excitation (n ranges from 42 to 82). The amplitude of the 140 ps pulse required for ionization of the Rb and Li Rydberg population is found to be a factor of two higher than the expected amplitude based on diabatic field ionization and recent theoretical calculations by Reinhold et al (1993 26 L659). Using the longer pulses we studied the transition from the diabatic/adabatic ionization towards ionization in the impulse-kick regime.

DOI
10.1088/0953-4075/30/6/016

Related papers

Short-pulse microwave ionization of Na Rydberg atoms

M. Gatzke, Bernard Broers, Lambertus D. Noordam +2 more

We have measured the microwave ionization threshold electric fields for ns-state Na Rydberg atoms from n=24--33 as a function of the duration of the ionizing microwave pulse. Pulses as short as 2.8 ns were used, containing fewer than 25 cycles of 8.55-GHz radiation. While the fields required to produce the onset of ionization were independent of pulse duration and exhibited the ${\mathit{n}}^{\mathrm{\ensuremath{-}}5}$ scaling characteristic of ionization by diffusion through higher-energy states, the fields required to produce nearly complete ionization increased dramatically as the pulse was shortened. Additional measurements of the populations of bound states after the shortest microwave pulses showed that up to \ensuremath{\sim}10% of the atoms were excited to states above the initially populated ns state and the adjacent (n-1) manifold of higher angular momentum states, while most either ionized or remained in these states. From this observation we conclude that the rate-limiting process for ionization is the transition from the initially populated ns states or the adjacent manifold to the next higher manifold, not the diffusion through higher-lying states.

Physical Review A•Sep 1, 1994•18 citations

Half-Cycle Microwave Excitation of Rubidium Rydberg Atoms

G. M. Lankhuijzen, Lambertus D. Noordam

Excitation from $\mathrm{ns}$, $\mathrm{np}$, and $\mathrm{nd}$ Rydberg states of rubidium to the adjacent manifolds by electrical pulses of 140 and 9 ns duration up to 200 V/cm is studied. These pulses correspond to half cycles of microwave fields of 2.6 GHz and 40 MHz. The observed population transfer (up to 40%) is not monotonically increasing with the field strength. For the 140 ps pulse local minima are found due to the absence of avoided crossings of appropriate size at the peak of the pulse. For the long pulses Stueckelberg oscillations are observed in the transfer yield.

Physical Review Letters•Jan 16, 1995•21 citations

Field ionization of Rydberg atoms in a single-cycle pulse

Baozhu Yang, F. Robicheaux

We study the ionization of Rydberg atoms in a single-cycle-pulse electric field based on both classical and quantum calculations. The ionization-probability curve exhibits a ``ripple'' structure as a function of the pulse duration and the field amplitude. These ripple structures are found to be dependent on the angular distribution of the initial state. A large electron-emission asymmetry is observed, and the ionized electron is almost completely emitted to one side of the atom except when the pulse length is roughly one Rydberg period. In both the long-pulse and the short-pulse regimes, larger electron energy can be expected from the ionization of lower-lying Rydberg states, matching the observation in a recent experiment [S. Li and R. R. Jones, Phys. Rev. Lett. 112, 143006 (2014)]. This trend is closely related to the electron-emission asymmetry associated with the field-direction change in a single-cycle pulse. The possible implications of the different energy transfer in a single-cycle pulse from that in a multicycle pulse are also discussed briefly for the strong-field ionization of the ground atomic state.

Physical Review A•Apr 13, 2015•18 citations

Ionization of Rydberg atoms by half-cycle pulses: effect of pulse shape and rise time

B. E. Tannian, Richard A. Popple, F. B. Dunning +3 more

The ionization of potassium np Rydberg atoms with $n\sim388$ by pulsed unidirectional electric fields, termed half-cycle pulses (HCPs), with various well-characterized shapes (rectangular, triangular, and sawtooth) and durations $T\sb{p}$ comparable to the classical electron orbital period $T\sb{n}$ is investigated. The experimental results are compared to classical trajectory Monte Carlo (CTMC) simulations and the classically-scaled results of quantum calculations undertaken at $n=5.$ The data show that in the intermediate regime, $T\sb{p}\sim T\sb{n},$ the threshold field for ionization becomes sensitive to the shape and rise time of the HCP, increasing with increasing rise time. For each pulse shape, the agreement between the experimental measurements and both the CTMC and quantum calculations is very good.

Journal of Physics B Atomic Molecular and Optical Physics•May 28, 1998•2 citations

Ionization of Rydberg atoms by half-cycle pulses

Carlos O Reinhold, Michael Melles, Hai Shao +1 more

We study the ionization of Rydberg atoms by half-cycle electromagnetic pulses as a function of the duration of the pulses covering a broad range of time intervals connecting the adiabatic and sudden regimes. The threshold fields for ionization lie on a universal classical scaling invariant curve. We present quantum mechanical results which agree well with the universal curve. The n -2 threshold field scaling found experimentally is a linear approximation to the universal curve by the tangent in the region where the pulse duration is of the order of the orbital period of the atom. We predict the existence of an ultrashort pulse limit in which the threshold field scales as n -1 . Effects due to the non-hydrogenic core are negligible.

Journal of Physics B Atomic Molecular and Optical Physics•Oct 14, 1993•83 citations

Basic Energy Sciences, under Award number DE-SC0012193.

Baochun Yang, F. Robicheaux

ization of Rydberg atoms by a single-cycle pulse, and also its implications for the strong field ionization of ground state. The required threshold field amplitude (for 10% ionization probability) scales inversely with the binding energy of initial states and also the pulse-duration square when the pulse duration becomes much shorter than the classical Rydberg period. A simple model is introduced to understand this threshold behavior, where the nonzero displacement induced by a single-cycle pulse plays a critical role. By combining with the adiabatic-ionization threshold in the low-frequency limit, an ionization window is expected for the ionization of different states. The ionization-probability curve exhibits a “ripple” structure as a function of the pulse duration and the field amplitude, which is sensitive to the angular distribution of initial states. The observation of larger emitted-electron energy for the ionization of lower-lying Rydberg states in a recent experiment [S Li and R. R. Jones, Phys. Rev. Lett. 112, 143006 (2014)] is confirmed in our calculations for both sodium and hydrogen atoms. The differences between the ionization dynamics in a single-cycle pulse and that in a multi-cycle pulse are also discussed and presented.

•Jan 1, 2015•0 citations
Ionization of Rydberg atoms by short, half-cycle electrical pulses is investigated experimentally in the intermediate-pulse duration regime where the ionization threshold fields are determined both by the slew rate of the ionizing pulse and its duration. Electrical pulses with durations ranging from 140 ps to 9 ns and amplitudes up to are applied to rubidium and lithium atoms prepared in high Rydberg states by laser excitation (n ranges from 42 to 82). The amplitude of the 140 ps pulse required for ionization of the Rb and Li Rydberg population is found to be a factor of two higher than the expected amplitude based on diabatic field ionization and recent theoretical calculations by Reinhold et al (1993 26 L659). Using the longer pulses we studied the transition from the diabatic/adabatic ionization towards ionization in the impulse-kick regime.
We have measured the microwave ionization threshold electric fields for ns-state Na Rydberg atoms from n=24--33 as a function of the duration of the ionizing microwave pulse. Pulses as short as 2.8 ns were used, containing fewer than 25 cycles of 8.55-GHz radiation. While the fields required to produce the onset of ionization were independent of pulse duration and exhibited the ${\mathit{n}}^{\mathrm{\ensuremath{-}}5}$ scaling characteristic of ionization by diffusion through higher-energy states, the fields required to produce nearly complete ionization increased dramatically as the pulse was shortened. Additional measurements of the populations of bound states after the shortest microwave pulses showed that up to \ensuremath{\sim}10% of the atoms were excited to states above the initially populated ns state and the adjacent (n-1) manifold of higher angular momentum states, while most either ionized or remained in these states. From this observation we conclude that the rate-limiting process for ionization is the transition from the initially populated ns states or the adjacent manifold to the next higher manifold, not the diffusion through higher-lying states.
Excitation from ns\mathrm{ns}ns, np\mathrm{np}np, and nd\mathrm{nd}nd Rydberg states of rubidium to the adjacent manifolds by electrical pulses of 140 and 9 ns duration up to 200 V/cm is studied. These pulses correspond to half cycles of microwave fields of 2.6 GHz and 40 MHz. The observed population transfer (up to 40%) is not monotonically increasing with the field strength. For the 140 ps pulse local minima are found due to the absence of avoided crossings of appropriate size at the peak of the pulse. For the long pulses Stueckelberg oscillations are observed in the transfer yield.
We study the ionization of Rydberg atoms in a single-cycle-pulse electric field based on both classical and quantum calculations. The ionization-probability curve exhibits a ``ripple'' structure as a function of the pulse duration and the field amplitude. These ripple structures are found to be dependent on the angular distribution of the initial state. A large electron-emission asymmetry is observed, and the ionized electron is almost completely emitted to one side of the atom except when the pulse length is roughly one Rydberg period. In both the long-pulse and the short-pulse regimes, larger electron energy can be expected from the ionization of lower-lying Rydberg states, matching the observation in a recent experiment [S. Li and R. R. Jones, Phys. Rev. Lett. 112, 143006 (2014)]. This trend is closely related to the electron-emission asymmetry associated with the field-direction change in a single-cycle pulse. The possible implications of the different energy transfer in a single-cycle pulse from that in a multicycle pulse are also discussed briefly for the strong-field ionization of the ground atomic state.
The ionization of potassium np Rydberg atoms with n∼388n\sim388n∼388 by pulsed unidirectional electric fields, termed half-cycle pulses (HCPs), with various well-characterized shapes (rectangular, triangular, and sawtooth) and durations $T\sb{p}$ comparable to the classical electron orbital period $T\sb{n}$ is investigated. The experimental results are compared to classical trajectory Monte Carlo (CTMC) simulations and the classically-scaled results of quantum calculations undertaken at n=5.n=5.n=5. The data show that in the intermediate regime, $T\sb{p}\sim T\sb{n},$ the threshold field for ionization becomes sensitive to the shape and rise time of the HCP, increasing with increasing rise time. For each pulse shape, the agreement between the experimental measurements and both the CTMC and quantum calculations is very good.
We study the ionization of Rydberg atoms by half-cycle electromagnetic pulses as a function of the duration of the pulses covering a broad range of time intervals connecting the adiabatic and sudden regimes. The threshold fields for ionization lie on a universal classical scaling invariant curve. We present quantum mechanical results which agree well with the universal curve. The n -2 threshold field scaling found experimentally is a linear approximation to the universal curve by the tangent in the region where the pulse duration is of the order of the orbital period of the atom. We predict the existence of an ultrashort pulse limit in which the threshold field scales as n -1 . Effects due to the non-hydrogenic core are negligible.
ization of Rydberg atoms by a single-cycle pulse, and also its implications for the strong field ionization of ground state. The required threshold field amplitude (for 10% ionization probability) scales inversely with the binding energy of initial states and also the pulse-duration square when the pulse duration becomes much shorter than the classical Rydberg period. A simple model is introduced to understand this threshold behavior, where the nonzero displacement induced by a single-cycle pulse plays a critical role. By combining with the adiabatic-ionization threshold in the low-frequency limit, an ionization window is expected for the ionization of different states. The ionization-probability curve exhibits a “ripple” structure as a function of the pulse duration and the field amplitude, which is sensitive to the angular distribution of initial states. The observation of larger emitted-electron energy for the ionization of lower-lying Rydberg states in a recent experiment [S Li and R. R. Jones, Phys. Rev. Lett. 112, 143006 (2014)] is confirmed in our calculations for both sodium and hydrogen atoms. The differences between the ionization dynamics in a single-cycle pulse and that in a multi-cycle pulse are also discussed and presented.