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

New Journal of Physics

Simultaneous deceleration of atoms and molecules in a supersonic beam

Nitzan Akerman, Michael Karpov, Liron David, Etay Lavert-Ofir, Julia Narevicius, Edvardas Narevicius

Published Jun 18, 2015• 19 citations
Publisher

Abstract

A unique property of Zeeman effect based manipulation of paramagnetic particle's motion is the ability to control velocities of both atoms and molecules. In particular the moving magnetic trap decelerator is capable of slowing and eventually trapping mixtures of both cold atoms and cold molecules generated in a supersonic expansion. Here we report the deceleration of molecular oxygen together with metastable argon atoms. The cold mixture with temperature below 1 K is slowed from an initial velocity of 430 m s −1 down to 100 m s −1 . Our decelerator spans 2.4 m and consists of 480 quadrupole traps. Our results pave the way for the study of sympathetic cooling of molecules by laser cooled atoms.

DOI
10.1088/1367-2630/17/6/065015

Related papers

Trapping of Molecular Oxygen together with Lithium Atoms

Nitzan Akerman, Michael Karpov, Yair Segev +3 more

We demonstrate simultaneous deceleration and trapping of a cold atomic and molecular mixture. This is the first step towards studies of cold atom-molecule collisions at low temperatures as well as application of sympathetic cooling. Both atoms and molecules are cooled in a supersonic expansion and are loaded into a moving magnetic trap that brings them to rest via the Zeeman interaction from an initial velocity of 375 m/s. We use a beam seeded with molecular oxygen, and entrain it with lithium atoms by laser ablation prior to deceleration. The deceleration ends with loading of the mixture into a static quadrupole trap, which is generated by two permanent magnets. We estimate 10^{9} trapped O_{2} molecules and 10^{5} Li atoms with background pressure limited lifetime on the order of 1 sec. With further improvements to lithium entrainment we expect that sympathetic cooling of molecules is within reach.

arXiv:1611.00155•Physical Review Letters•Aug 16, 2017•56 citations

A moving magnetic trap decelerator: a new source of cold atoms and molecules

Etay Lavert-Ofir, Sasha Gersten, Alon Henson +4 more

We present an experimental realization of a moving magnetic trap decelerator, where paramagnetic particles entrained in a cold supersonic beam are decelerated in a co-moving magnetic trap.Our method allows for an efficient slowing down of both paramagnetic atoms and molecules to near stopping velocities.We show that under realistic conditions we will be able to trap and decelerate a large fraction of the initial supersonic beam.We present our first results on deceleration in a moving magnetic trap by bringing metastable neon atoms to near rest.Our estimated phase space volume occupied by decelerated particles at a final velocity of 50 m s -1 shows an improvement of two orders of magnitude as compared to currently available deceleration techniques.Cold chemistry (at temperature of ∼1 K) is a fast developing field with many interesting theoretical predictions yet only a few experiments [1][2][3][4].It has been predicted that in the cold chemistry regime, reactions might proceed through resonance states [5] and both reaction rate and path could be controlled [6] via external magnetic or electrostatic fields.Low-temperature chemistry is not limited to artificially created conditions alone but occurs naturally at the low temperature of interstellar space [7] and the atmospheres of remote planets and moons [8].It is anticipated that cold chemistry will follow the enormous progress in molecular chemistry that was spurred by the advent of supersonic beams more than half a century ago [9].However, the progress in experimental cold chemistry is rather slow partly due to the absence of a general method of atomic and molecular cooling.Although the low-temperature environment created within a supersonic expansion has been used to observe many reactions [10], a direct 1 Author to whom any correspondence should be addressed.

arXiv:1011.0418•New Journal of Physics•Oct 24, 2011•51 citations

A Moving-Trap Zeeman Decelerator

McArd, Lewis A., Arin Mizouri, Walker, Paul A. +4 more

We present a moving-trap Zeeman decelerator (MTZD) for use in molecular beam manipulation and magnetic-trapping experiments of paramagnetic atoms and molecules. The 0.49 m MTZD consists of a combination of a 2D magnetic quadrupole guide and deceleration coils, which together produce an array of 3D magnetic traps. The design is based on that of Trimeche et al. with significant modifications. The 2D quadrupole is driven by fast rising and falling square pulses of current (up to 700 A) of arbitrary lengths of time. The traps can be made to move at velocities from ca. 370 m/s down to zero, which is done by driving through the deceleration coils a sinusoidal current with frequencies ranging from zero to ca. 9 kHz and peak currents up to 1000 A. The trap velocity is proportional to the current frequency. The MTZD manipulates the velocities of molecular beams by traveling initially at the same velocity as the beam. 3D guiding is achieved with a constant current frequency and deceleration is achieved with a downward chirp of the current frequency at a rate corresponding to the desired deceleration. We explain the technical design and operation principles of the MTZD and we detail the custom power electronics that drive the 2D quadrupole guide and the decelerator coils. We present extensive Monte-Carlo trajectory simulations to demonstrate the properties of the MTZD and we conclude that decelerations should be kept below 30000 m/s/s to maintain a good 6D phase-space acceptance. In proof-of-principle experiments, with the deceleration coils operating with a reduced current in the range 100-200 A, we demonstrate the 3D guiding of a beam of metastable argon atoms at 373 m/s and deceleration at 25000 m/s/s from 342 m/s to 304 m/s. The deceleration corresponds to the removal of 21% of the kinetic energy of the beam.

arXiv:1807.10648•Jul 27, 2018•4 citations

One-dimensional confinement of magnetically decelerated supersonic beams of O2 molecules

Yang Liu, Sida Zhou, Wei Zhong +2 more

We have demonstrated that supersonic beams of oxygen molecules $({\text{O}}_{2})$ in the ground rotational state were slowed to a near standstill by a linear Zeeman decelerator and successfully confined spatially in an anti-Helmholtz magnetic trap. The translational temperature of the decelerated ${\text{O}}_{2}$ molecules was about 800 mK. The demonstrated trapping capability of paramagnetic species opens up various possibilities for the investigation of cold collisions and reactions of various radicals in the sub-kelvin regime by spatially confining them in a magnetic trap.

Physical Review A•Feb 27, 2015•23 citations

Magnetic Trapping of Hydrogen after Multistage Zeeman Deceleration

S. D. Hogan, A. W. Wiederkehr, Hansjürg Schmutz +1 more

We report the first experimental realization of magnetic trapping of a sample of cold radicals following multistage Zeeman deceleration of a pulsed supersonic beam. H atoms seeded in a supersonic expansion of Kr have been decelerated from an initial velocity of 520 m/s to 100 m/s in a 12-stage Zeeman decelerator and loaded into a magnetic quadrupole trap by rapidly switching the fields of the trap solenoids.

Physical Review Letters•Sep 29, 2008•92 citations

Multistage Zeeman deceleration of atoms and molecules

A. W. Wiederkehr

A modular multistage Zeeman decelerator consisting of an array of solenoids has been developed to control the velocity of cold, paramagnetic atoms and molecules in supersonic beams. The translational motion these atoms and molecules was manipulated with high precision by exploiting the interaction between their magnetic moments and timedependent inhomogeneous magnetic elds. Deceleration was achieved by pulsing high currents (up to 300 A) through the solenoids of the decelerator with pulse sequences calculated to preserve the phase-space density of the atomic and molecular samples while removing a preset amount of kinetic energy. For the operation of the multistage Zeeman decelerator, solenoids and electronic units were developed to generate strong magneticeld pulses (> 2 T) with rise and fall times of only a few microseconds. An accurate three-dimensional particle-trajectory simulation program has been developed to analyze the deceleration process and optimize its e ciency. This software was thoroughly tested by systematic comparison with experimental results and enabled, in combination with measurements, the complete characterization of the spatial and velocity distributions of the decelerated and trapped atoms for di erent sets of experimental conditions. The program was essential to achieve a complete interpretation of the dynamics of the deceleration process and to devise a strategy to e ciently load the decelerated atoms and molecules into magnetic quadrupole traps. In a rst experiment, hydrogen atoms seeded in a supersonic expansion of Kr have been decelerated from an initial velocity of 435 m/s to nal velocities as low as 107 m/s in a 12-stage Zeeman decelerator. The operation of the decelerator has been analyzed by comparing the results of numerical particle-trajectory simulations with those of independent measurements of the velocity distribution by ion time-ofight mass spectrometry following photoionization of the decelerated atoms. The velocity distribution of the decelerated atom cloud was found to have a half width at half maximum of 25± 12 m/s corresponding to a temperature of ∼ 40 mK. The phase stability of the multistage-Zeeman-deceleration process has been investigated by numerical particle-trajectory simulations and experimental measurements on deuterium atoms in a 24-stage Zeeman decelerator. A one-dimensional analytical model of the phase stability in a multistage Zeeman decelerator was adapted from a one-dimensional model of phase stability in a multistage Stark decelerator and compared with the results of oneand three-dimensional particle-trajectory simulations. The comparison, which included the analysis of the e ects of nite switch-on and switch-o times of the deceleration pulses, revealed that transverse e ects in the decelerator lead to a considerable reduction of the

•Jan 1, 2012•0 citations
A unique property of Zeeman effect based manipulation of paramagnetic particle's motion is the ability to control velocities of both atoms and molecules. In particular the moving magnetic trap decelerator is capable of slowing and eventually trapping mixtures of both cold atoms and cold molecules generated in a supersonic expansion. Here we report the deceleration of molecular oxygen together with metastable argon atoms. The cold mixture with temperature below 1 K is slowed from an initial velocity of 430 m s −1 down to 100 m s −1 . Our decelerator spans 2.4 m and consists of 480 quadrupole traps. Our results pave the way for the study of sympathetic cooling of molecules by laser cooled atoms.
We demonstrate simultaneous deceleration and trapping of a cold atomic and molecular mixture. This is the first step towards studies of cold atom-molecule collisions at low temperatures as well as application of sympathetic cooling. Both atoms and molecules are cooled in a supersonic expansion and are loaded into a moving magnetic trap that brings them to rest via the Zeeman interaction from an initial velocity of 375 m/s. We use a beam seeded with molecular oxygen, and entrain it with lithium atoms by laser ablation prior to deceleration. The deceleration ends with loading of the mixture into a static quadrupole trap, which is generated by two permanent magnets. We estimate 10^{9} trapped O_{2} molecules and 10^{5} Li atoms with background pressure limited lifetime on the order of 1 sec. With further improvements to lithium entrainment we expect that sympathetic cooling of molecules is within reach.
We present an experimental realization of a moving magnetic trap decelerator, where paramagnetic particles entrained in a cold supersonic beam are decelerated in a co-moving magnetic trap.Our method allows for an efficient slowing down of both paramagnetic atoms and molecules to near stopping velocities.We show that under realistic conditions we will be able to trap and decelerate a large fraction of the initial supersonic beam.We present our first results on deceleration in a moving magnetic trap by bringing metastable neon atoms to near rest.Our estimated phase space volume occupied by decelerated particles at a final velocity of 50 m s -1 shows an improvement of two orders of magnitude as compared to currently available deceleration techniques.Cold chemistry (at temperature of ∼1 K) is a fast developing field with many interesting theoretical predictions yet only a few experiments [1][2][3][4].It has been predicted that in the cold chemistry regime, reactions might proceed through resonance states [5] and both reaction rate and path could be controlled [6] via external magnetic or electrostatic fields.Low-temperature chemistry is not limited to artificially created conditions alone but occurs naturally at the low temperature of interstellar space [7] and the atmospheres of remote planets and moons [8].It is anticipated that cold chemistry will follow the enormous progress in molecular chemistry that was spurred by the advent of supersonic beams more than half a century ago [9].However, the progress in experimental cold chemistry is rather slow partly due to the absence of a general method of atomic and molecular cooling.Although the low-temperature environment created within a supersonic expansion has been used to observe many reactions [10], a direct 1 Author to whom any correspondence should be addressed.
We present a moving-trap Zeeman decelerator (MTZD) for use in molecular beam manipulation and magnetic-trapping experiments of paramagnetic atoms and molecules. The 0.49 m MTZD consists of a combination of a 2D magnetic quadrupole guide and deceleration coils, which together produce an array of 3D magnetic traps. The design is based on that of Trimeche et al. with significant modifications. The 2D quadrupole is driven by fast rising and falling square pulses of current (up to 700 A) of arbitrary lengths of time. The traps can be made to move at velocities from ca. 370 m/s down to zero, which is done by driving through the deceleration coils a sinusoidal current with frequencies ranging from zero to ca. 9 kHz and peak currents up to 1000 A. The trap velocity is proportional to the current frequency. The MTZD manipulates the velocities of molecular beams by traveling initially at the same velocity as the beam. 3D guiding is achieved with a constant current frequency and deceleration is achieved with a downward chirp of the current frequency at a rate corresponding to the desired deceleration. We explain the technical design and operation principles of the MTZD and we detail the custom power electronics that drive the 2D quadrupole guide and the decelerator coils. We present extensive Monte-Carlo trajectory simulations to demonstrate the properties of the MTZD and we conclude that decelerations should be kept below 30000 m/s/s to maintain a good 6D phase-space acceptance. In proof-of-principle experiments, with the deceleration coils operating with a reduced current in the range 100-200 A, we demonstrate the 3D guiding of a beam of metastable argon atoms at 373 m/s and deceleration at 25000 m/s/s from 342 m/s to 304 m/s. The deceleration corresponds to the removal of 21% of the kinetic energy of the beam.
We have demonstrated that supersonic beams of oxygen molecules (O2)({\text{O}}_{2})(O2​) in the ground rotational state were slowed to a near standstill by a linear Zeeman decelerator and successfully confined spatially in an anti-Helmholtz magnetic trap. The translational temperature of the decelerated O2{\text{O}}_{2}O2​ molecules was about 800 mK. The demonstrated trapping capability of paramagnetic species opens up various possibilities for the investigation of cold collisions and reactions of various radicals in the sub-kelvin regime by spatially confining them in a magnetic trap.
A modular multistage Zeeman decelerator consisting of an array of solenoids has been developed to control the velocity of cold, paramagnetic atoms and molecules in supersonic beams. The translational motion these atoms and molecules was manipulated with high precision by exploiting the interaction between their magnetic moments and timedependent inhomogeneous magnetic elds. Deceleration was achieved by pulsing high currents (up to 300 A) through the solenoids of the decelerator with pulse sequences calculated to preserve the phase-space density of the atomic and molecular samples while removing a preset amount of kinetic energy. For the operation of the multistage Zeeman decelerator, solenoids and electronic units were developed to generate strong magneticeld pulses (> 2 T) with rise and fall times of only a few microseconds. An accurate three-dimensional particle-trajectory simulation program has been developed to analyze the deceleration process and optimize its e ciency. This software was thoroughly tested by systematic comparison with experimental results and enabled, in combination with measurements, the complete characterization of the spatial and velocity distributions of the decelerated and trapped atoms for di erent sets of experimental conditions. The program was essential to achieve a complete interpretation of the dynamics of the deceleration process and to devise a strategy to e ciently load the decelerated atoms and molecules into magnetic quadrupole traps. In a rst experiment, hydrogen atoms seeded in a supersonic expansion of Kr have been decelerated from an initial velocity of 435 m/s to nal velocities as low as 107 m/s in a 12-stage Zeeman decelerator. The operation of the decelerator has been analyzed by comparing the results of numerical particle-trajectory simulations with those of independent measurements of the velocity distribution by ion time-ofight mass spectrometry following photoionization of the decelerated atoms. The velocity distribution of the decelerated atom cloud was found to have a half width at half maximum of 25± 12 m/s corresponding to a temperature of ∼ 40 mK. The phase stability of the multistage-Zeeman-deceleration process has been investigated by numerical particle-trajectory simulations and experimental measurements on deuterium atoms in a 24-stage Zeeman decelerator. A one-dimensional analytical model of the phase stability in a multistage Zeeman decelerator was adapted from a one-dimensional model of phase stability in a multistage Stark decelerator and compared with the results of oneand three-dimensional particle-trajectory simulations. The comparison, which included the analysis of the e ects of nite switch-on and switch-o times of the deceleration pulses, revealed that transverse e ects in the decelerator lead to a considerable reduction of the