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

arXiv:1607.04844 · Science Advances

Molecular beam brightening by shock-wave suppression

Yair Segev, Natan Bibelnik, Nitzan Akerman, Yuval Shagam, Alon Luski, Michael Karpov, Julia Narevicius, Edvardas Narevicius

Published Mar 3, 2017• 1 citation
arXivHTMLPDF

Abstract

We defeat the fundamental limit on molecular beam flux by cooling interacting surfaces, eliminating disruptive shock waves.
DOI
10.1126/sciadv.1602258

Related papers

Molecular collision studies with Stark-decelerated beams

Gerard Meijer

Bulletin of the American Physical Society•Mar 10, 2008•0 citations

Molecular beam brightening by shock-wave suppression.

Yair Segev, Natan Bibelnik, Nitzan Akerman +5 more

Supersonic beams are a prevalent source of cold molecules used in the study of chemical reactions, atom interferometry, gas-surface interactions, precision spectroscopy, molecular cooling, and more. The triumph of this method emanates from the high densities produced in relation to other methods; however, beam density remains fundamentally limited by interference with shock waves reflected from collimating surfaces. We show experimentally that this shock interaction can be reduced or even eliminated by cryocooling the interacting surface. An increase of nearly an order of magnitude in beam density was measured at the lowest surface temperature, with no further fundamental limitation reached. Visualization of the shock waves by plasma discharge and reproduction with direct simulation Monte Carlo calculations both indicate that the suppression of the shock structure is partially caused by lowering the momentum flux of reflected particles and significantly enhanced by the adsorption of particles to the surface. We observe that the scaling of beam density with source pressure is recovered, paving the way to order-of-magnitude brighter, cold molecular beams.

•Mar 1, 2017•18 citations

Shock wave loading of a magnetic guide

L. Kindt

The atom laser has long been a holy grail within atom physics and with the creation of an atom laser we hope to bring a similar revolution in to the field of atom optics. With the creation of the Bose-Einstein Condensate (BEC) in 1995 the path to an atom laser was initiated. An atom laser is continues source of BEC. In a Bose condensate all the atoms occupy the same quantum state and can be described by the same wave function and phase. With an atom laser the De Broglie wavelength of atoms can be much smaller than the wavelength of light. Due to the ultimate control over the atoms the atom laser is very interesting for atom optics, lithography, metrology, etching and deposition of atoms on a surface. All previous atom lasers have been created from atoms coupled out from an existing Bose-Einstein Condensate. There are different approaches but common to them all is that the duration of the output of the atom laser is limited by the size of the initial BEC and they all have a low flux. This leaves the quest to build a continuous high flux atom laser. An alternative approach to a continuous BEC beam is to channel a continuous ultra cold atomic beam into a magnetic guide and then cool this beam down to degeneracy. Cooling down a continuous beam of atoms faces three large problems: The collision rate has to be large enough for effective rethermalization, since evaporative cooling in 2D is not as effective as in 3D and a large thermal conductivity due to atoms with a high angular momentum causes heating downstream in the guide. We have built a 4 meter magnetic guide that is placed on a downward slope with a magnetic barrier in the end. In the guide we load packets of ultra cold rubidium atoms with a frequency rate large enough for the packets to merge together to form a continuous atomic beam. The atomic beam is supersonic and when the beam reaches the end barrier it will return and collide with itself. The collisions lowers the velocity of the beam into subsonic velocities and a shock wave is created between the two velocity regions. In order to conserve number of particle, momentum and enthalpy the density of the atomic beam passing through the shock wave must increase. We have build such a shock wave in an atomic beam and observed the density increase due to this. As an extra feature having a subsonic beam on a downward slope adds an extra density increase due to gravitational compression. Loading ultra cold atoms into a 3D trap from the dense subsonic beam overcomes the problem with 2D cooling and thermal conductivity. This was done and evaporative cooling was applied creating an unprecedented large number rubidium BEC.

•Oct 21, 2011•1 citation

Production and all-optical deceleration of molecular beams

Gary Chen, Andrew M. Jayich, Xueping Long +2 more

Bulletin of the American Physical Society•Jun 9, 2015•0 citations

Cold atomic and molecular beams using buffer-gas cooling

Nathaniel Brahms, David R. Glenn, Robert deCarvalho +4 more

APS•May 1, 2004•0 citations

A Complex atom lens

Erik Anciaux

This dissertation presents progress on an atomic beam brightening and focusing experiment that has been shown to create a beam with higher brightness and greater resolution than that of any previous atomic focusing experiment. Our method of beam brightening relies upon using a permanent magnetic hexapole as a lens in conjunction with transverse laser cooling to focus and collimate a supersonic beam of metastable neon atoms. We then use an adjustable electromagnetic hexapole as a lens to focus the brightened atomic beam. Neutral atom beams have long been used as a tool to spectroscopically probe two dimensional surfaces, however the lack of a means to create bright, high-resolution neutral atom beams has limited their utility as a nanoscale resolution probing mechanism. While optical and electron microscopy have been the workhorses of microscopy for decades, we believe that our scheme for beam brightening and focusing will unleash the promise of neutral atom microscopy. Our scheme of beam brightening and focusing can be repeated in series and reveals a pathway to true high density nanoscale neutral atom focusing. Simulations suggest that when combined with aberration correction, our scheme will be able to produce an atomic beam with sufficient brightness and resolution to be useful as a surface sensitive nanoscale probe.

•Jan 1, 2018•0 citations
Supersonic beams are a prevalent source of cold molecules used in the study of chemical reactions, atom interferometry, gas-surface interactions, precision spectroscopy, molecular cooling, and more. The triumph of this method emanates from the high densities produced in relation to other methods; however, beam density remains fundamentally limited by interference with shock waves reflected from collimating surfaces. We show experimentally that this shock interaction can be reduced or even eliminated by cryocooling the interacting surface. An increase of nearly an order of magnitude in beam density was measured at the lowest surface temperature, with no further fundamental limitation reached. Visualization of the shock waves by plasma discharge and reproduction with direct simulation Monte Carlo calculations both indicate that the suppression of the shock structure is partially caused by lowering the momentum flux of reflected particles and significantly enhanced by the adsorption of particles to the surface. We observe that the scaling of beam density with source pressure is recovered, paving the way to order-of-magnitude brighter, cold molecular beams.
The atom laser has long been a holy grail within atom physics and with the creation of an atom laser we hope to bring a similar revolution in to the field of atom optics. With the creation of the Bose-Einstein Condensate (BEC) in 1995 the path to an atom laser was initiated. An atom laser is continues source of BEC. In a Bose condensate all the atoms occupy the same quantum state and can be described by the same wave function and phase. With an atom laser the De Broglie wavelength of atoms can be much smaller than the wavelength of light. Due to the ultimate control over the atoms the atom laser is very interesting for atom optics, lithography, metrology, etching and deposition of atoms on a surface. All previous atom lasers have been created from atoms coupled out from an existing Bose-Einstein Condensate. There are different approaches but common to them all is that the duration of the output of the atom laser is limited by the size of the initial BEC and they all have a low flux. This leaves the quest to build a continuous high flux atom laser. An alternative approach to a continuous BEC beam is to channel a continuous ultra cold atomic beam into a magnetic guide and then cool this beam down to degeneracy. Cooling down a continuous beam of atoms faces three large problems: The collision rate has to be large enough for effective rethermalization, since evaporative cooling in 2D is not as effective as in 3D and a large thermal conductivity due to atoms with a high angular momentum causes heating downstream in the guide. We have built a 4 meter magnetic guide that is placed on a downward slope with a magnetic barrier in the end. In the guide we load packets of ultra cold rubidium atoms with a frequency rate large enough for the packets to merge together to form a continuous atomic beam. The atomic beam is supersonic and when the beam reaches the end barrier it will return and collide with itself. The collisions lowers the velocity of the beam into subsonic velocities and a shock wave is created between the two velocity regions. In order to conserve number of particle, momentum and enthalpy the density of the atomic beam passing through the shock wave must increase. We have build such a shock wave in an atomic beam and observed the density increase due to this. As an extra feature having a subsonic beam on a downward slope adds an extra density increase due to gravitational compression. Loading ultra cold atoms into a 3D trap from the dense subsonic beam overcomes the problem with 2D cooling and thermal conductivity. This was done and evaporative cooling was applied creating an unprecedented large number rubidium BEC.
This dissertation presents progress on an atomic beam brightening and focusing experiment that has been shown to create a beam with higher brightness and greater resolution than that of any previous atomic focusing experiment. Our method of beam brightening relies upon using a permanent magnetic hexapole as a lens in conjunction with transverse laser cooling to focus and collimate a supersonic beam of metastable neon atoms. We then use an adjustable electromagnetic hexapole as a lens to focus the brightened atomic beam. Neutral atom beams have long been used as a tool to spectroscopically probe two dimensional surfaces, however the lack of a means to create bright, high-resolution neutral atom beams has limited their utility as a nanoscale resolution probing mechanism. While optical and electron microscopy have been the workhorses of microscopy for decades, we believe that our scheme for beam brightening and focusing will unleash the promise of neutral atom microscopy. Our scheme of beam brightening and focusing can be repeated in series and reveals a pathway to true high density nanoscale neutral atom focusing. Simulations suggest that when combined with aberration correction, our scheme will be able to produce an atomic beam with sufficient brightness and resolution to be useful as a surface sensitive nanoscale probe.