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:quant-ph/0703155 · Physical Review A

Trapping cold atoms near carbon nanotubes: Thermal spin flips and Casimir-Polder potential

R. Fermani, Stefan Scheel, P. L. Knight

Published Jun 28, 2007• 49 citations
arXivHTMLPDF

Abstract

We investigate the possibility of trapping ultracold $^{87}\mathrm{Rb}$ atoms near the outside of a metallic carbon nanotube, which we imagine using as a miniaturized current-carrying wire. We calculate atomic spin-flip lifetimes and compare the strength of the Casimir-Polder potential with the magnetic trapping potential. Our analysis indicates that the Casimir-Polder force is the dominant loss mechanism, and we compute the minimum distance to the carbon nanotube at which the atoms can be trapped to be larger than $100\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$.

DOI
10.1103/physreva.75.062905

Related papers

Tuning Casimir-Polder Interactions in Alkali BEC Atoms via Carbon Nanotube Geometry: A Comparative Study of [Li, Na, Cs, Rb]

Ahmad Firdaus Khaidir, Mohamad Nazri Abdul Halif, Zulfi Abdullah +3 more

Atom-surface dispersion has become a subject of studies involving the process of efficient trapping and manipulating ultracold alkali atoms, Bose-Einstein Condensation (BEC) near the carbon nanotubes (CNT). Known as Casimir-Polder (CP) interaction, it has been approximated as analytical expression using Hamaker's approach of pairwise summation (PWS) by summing up every contribution imposed by ground state BEC treated as single atom over densely packed atoms inside CNT. At larger atom-surface distances, the CP interaction is found to be strikingly weaker on a cylindrical shell compared to a solid cylinder, with this weakening increasing further as the alkali atoms become much lighter. We examine how these results will be beneficial to BEC experiment especially when cold atoms are magnetically or optically trapped above a relatively few microns-distance CNT atom chip, fabricated as a pristine graphene and sustained under high vacuum conditions.

IEEE International Conference on Sensors and Nanotechnology (SENNANO)•Sep 10, 2025•0 citations

Atomic relaxation processes near conducting and superconducting surfaces

R. Fermani

The aim of this thesis is to investigate the interaction of neutral atoms with conducting and superconducting surfaces. Experimental advances in the magnetic confinement of ultracold atoms have shown that they can act as a powerful tool in a wide range of phenomena such as electric and magnetic field imaging and matter wave interferometry. Coherent manipulation of atoms and ever smaller magnetic traps are essential elements in the implementation of integrated quantum devices for fundamental research, quantum information processing and precision measurements. This thesis considers main influences on atoms placed within three different environments which are useful in achieving miniaturization and efficient control in atomic magnetic traps: carbon nanotubes, dielectric surfaces and superconducting thin films. The possibility of holding atoms near the outside of a carbon nanotubes will be addressed. In order to give a qualitative analysis of the atom-nanotube interaction, thermally induced spin-flips and the Casimir-Polder potential have been considered. The comparison between these two effects is presented in this thesis. It indicates that the Casimir-Polder force is the dominant loss mechanism and an estimation of the minimum trapping distance is given based on its effect. Secondly, a first-principles derivation of spatial atomic-sublevel decoherence near dielectric and metallic surfaces will be presented. The rate obtained for the decay of spatial coherence has dual implications, on one hand, it can be considered as a measure of the coherence length of the fluctuations of the electromagnetic field arising from a given substrate. On the other hand, it turns out to be relevant for quantum information encoding in double well potentials. Finally, the known spin-flip transition rate will be linked to the flux noise spectrum in superconducting thin films showing the feasibility of using cold atomic clouds in the investigation of vortex dynamics.

•Jan 1, 2008•0 citations

Nanowire atomchip traps for sub-micron atom–surface distances

R Salem, Y Japha, Julien Chabé +4 more

We present an analysis of magnetic traps for ultracold atoms based on current-carrying wires with sub-micron dimensions. We analyze the physical limitations of these conducting wires as well as how such miniaturized magnetic traps are affected by the nearby surface due to tunneling to the surface, surface thermal noise, electron scattering within the wire and the Casimir–Polder force. We show that wires with cross sections as small as a few tens of nanometers should enable robust operating conditions for coherent atom optics (e.g. tunneling barriers for interferometry). In particular, trap sizes of the order of the de Broglie wavelength become accessible, based solely on static magnetic fields, thereby bringing the atomchip a step closer to fulfilling its promise of a compact device for complex and accurate quantum optics with ultracold atoms.

arXiv:0910.2598•New Journal of Physics•Feb 26, 2010•35 citations

Immersing carbon nanotubes in cold atomic gases

C. T. Weiß, Polina V. Mironova, József Fortágh +2 more

We investigate the sympathetic relaxation of a free-standing, vibrating carbon nanotube that is mounted on an atom chip and is immersed in a cloud of ultracold atoms. Gas atoms colliding with the nanotube excite phonons via a Casimir-Polder potential. We use Fermi's golden rule to estimate the relaxation rates for relevant experimental parameters and develop a fully dynamic theory of relaxation for the multimode phononic field embedded in a thermal atomic reservoir. Based on currently available experimental data, we identify the relaxation rates as a function of atom density and temperature that are required for sympathetic ground-state cooling of carbon nanotubes.

arXiv:1307.2096•Physical Review A•Oct 17, 2013•6 citations

Multi-Cell Traps for Registering of Cold Atom Clouds

Guennadi A. Kouzaev, KARL J. SAND

In this letter, the results on the development and simulation of new three-dimensional nanotraps for cold dressed atoms are considered. The traps are the multi-cell structures built by crossed non-touching carbon nanotubes. The trapping effect is tuned by the DC and RF currents to confine the strong- or low-potential seeking atoms far enough from the areas of strong Casimir-Polder and spin-flip forces. It is supposed that the developed and simulated multi-cell structures are pertinent for catching the Bose-Einstein condensates to demonstrate the Josephson effect, and to enable the study of the entanglement of confined clouds in three-dimensional nano-cells.

arXiv:0802.4355•Feb 29, 2008•0 citations

Thermal spin flips in atom chips

Per Kristian Rekdal, Stefan Scheel, P. L. Knight +1 more

We derive a general expression for the spin-flip rate of an atom trapped near an arbitrary dielectric body and we apply this theory to the case of a two-layer cylindrical metal wire. The spin-flip lifetimes we calculate are compared with those expected for an atom near a metallic slab and with those measured by Jones et al. above a two-layer wire [M.P.A. Jones, C.J. Vale, D. Sahagun, B.V. Hall, and E.A. Hinds, Phys. Rev. Lett. 91, 080401 (2003)]. We investigate how the lifetime depends on the skin depth of the material and on the scaling of the dimensions. This leads us to some conclusions about the design of integrated circuits for manipulating ultracold atoms (atom chips).

arXiv:quant-ph/0403166•Physical Review A•Jul 28, 2004•79 citations
We investigate the possibility of trapping ultracold 87Rb^{87}\mathrm{Rb}87Rb atoms near the outside of a metallic carbon nanotube, which we imagine using as a miniaturized current-carrying wire. We calculate atomic spin-flip lifetimes and compare the strength of the Casimir-Polder potential with the magnetic trapping potential. Our analysis indicates that the Casimir-Polder force is the dominant loss mechanism, and we compute the minimum distance to the carbon nanotube at which the atoms can be trapped to be larger than 100nm100\phantom{\rule{0.3em}{0ex}}\mathrm{nm}100nm.
Atom-surface dispersion has become a subject of studies involving the process of efficient trapping and manipulating ultracold alkali atoms, Bose-Einstein Condensation (BEC) near the carbon nanotubes (CNT). Known as Casimir-Polder (CP) interaction, it has been approximated as analytical expression using Hamaker's approach of pairwise summation (PWS) by summing up every contribution imposed by ground state BEC treated as single atom over densely packed atoms inside CNT. At larger atom-surface distances, the CP interaction is found to be strikingly weaker on a cylindrical shell compared to a solid cylinder, with this weakening increasing further as the alkali atoms become much lighter. We examine how these results will be beneficial to BEC experiment especially when cold atoms are magnetically or optically trapped above a relatively few microns-distance CNT atom chip, fabricated as a pristine graphene and sustained under high vacuum conditions.
The aim of this thesis is to investigate the interaction of neutral atoms with conducting and superconducting surfaces. Experimental advances in the magnetic confinement of ultracold atoms have shown that they can act as a powerful tool in a wide range of phenomena such as electric and magnetic field imaging and matter wave interferometry. Coherent manipulation of atoms and ever smaller magnetic traps are essential elements in the implementation of integrated quantum devices for fundamental research, quantum information processing and precision measurements. This thesis considers main influences on atoms placed within three different environments which are useful in achieving miniaturization and efficient control in atomic magnetic traps: carbon nanotubes, dielectric surfaces and superconducting thin films. The possibility of holding atoms near the outside of a carbon nanotubes will be addressed. In order to give a qualitative analysis of the atom-nanotube interaction, thermally induced spin-flips and the Casimir-Polder potential have been considered. The comparison between these two effects is presented in this thesis. It indicates that the Casimir-Polder force is the dominant loss mechanism and an estimation of the minimum trapping distance is given based on its effect. Secondly, a first-principles derivation of spatial atomic-sublevel decoherence near dielectric and metallic surfaces will be presented. The rate obtained for the decay of spatial coherence has dual implications, on one hand, it can be considered as a measure of the coherence length of the fluctuations of the electromagnetic field arising from a given substrate. On the other hand, it turns out to be relevant for quantum information encoding in double well potentials. Finally, the known spin-flip transition rate will be linked to the flux noise spectrum in superconducting thin films showing the feasibility of using cold atomic clouds in the investigation of vortex dynamics.
We present an analysis of magnetic traps for ultracold atoms based on current-carrying wires with sub-micron dimensions. We analyze the physical limitations of these conducting wires as well as how such miniaturized magnetic traps are affected by the nearby surface due to tunneling to the surface, surface thermal noise, electron scattering within the wire and the Casimir–Polder force. We show that wires with cross sections as small as a few tens of nanometers should enable robust operating conditions for coherent atom optics (e.g. tunneling barriers for interferometry). In particular, trap sizes of the order of the de Broglie wavelength become accessible, based solely on static magnetic fields, thereby bringing the atomchip a step closer to fulfilling its promise of a compact device for complex and accurate quantum optics with ultracold atoms.
We investigate the sympathetic relaxation of a free-standing, vibrating carbon nanotube that is mounted on an atom chip and is immersed in a cloud of ultracold atoms. Gas atoms colliding with the nanotube excite phonons via a Casimir-Polder potential. We use Fermi's golden rule to estimate the relaxation rates for relevant experimental parameters and develop a fully dynamic theory of relaxation for the multimode phononic field embedded in a thermal atomic reservoir. Based on currently available experimental data, we identify the relaxation rates as a function of atom density and temperature that are required for sympathetic ground-state cooling of carbon nanotubes.
In this letter, the results on the development and simulation of new three-dimensional nanotraps for cold dressed atoms are considered. The traps are the multi-cell structures built by crossed non-touching carbon nanotubes. The trapping effect is tuned by the DC and RF currents to confine the strong- or low-potential seeking atoms far enough from the areas of strong Casimir-Polder and spin-flip forces. It is supposed that the developed and simulated multi-cell structures are pertinent for catching the Bose-Einstein condensates to demonstrate the Josephson effect, and to enable the study of the entanglement of confined clouds in three-dimensional nano-cells.
We derive a general expression for the spin-flip rate of an atom trapped near an arbitrary dielectric body and we apply this theory to the case of a two-layer cylindrical metal wire. The spin-flip lifetimes we calculate are compared with those expected for an atom near a metallic slab and with those measured by Jones et al. above a two-layer wire [M.P.A. Jones, C.J. Vale, D. Sahagun, B.V. Hall, and E.A. Hinds, Phys. Rev. Lett. 91, 080401 (2003)]. We investigate how the lifetime depends on the skin depth of the material and on the scaling of the dimensions. This leads us to some conclusions about the design of integrated circuits for manipulating ultracold atoms (atom chips).