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

Physical Review A

Enhanced magnetic resonance signal of spin-polarized Rb atoms near surfaces of coated cells

Kaifeng Zhao, Martin Schaden, Z. Wu

Published Apr 21, 2010• 71 citations
Publisher

Abstract

We present a detailed experimental and theoretical study of edge enhancement in optically pumped Rb vapor in coated cylindrical pyrex glass cells. The Zeeman polarization of Rb atoms is produced and probed in the vicinity ($~$${10}^{\ensuremath{-}4}$ cm) of the cell surface by evanescent pump and probe beams. Spin-polarized Rb atoms diffuse throughout the cell in the presence of magnetic field gradients. In the present experiment the edge enhanced signal from the back surface of the cell is suppressed compared to that from the front surface, due to the fact that polarization is probed by the evanescent wave at the front surface only. The observed magnetic resonance line shape is reproduced quantitatively by a theoretical model and yields information about the dwell time and relaxation probability of Rb atoms on Pyrex glass surfaces coated with antirelaxation coatings.

DOI
10.1103/physreva.81.042903

Related papers

Method for measuring surface-interaction parameters of spin-polarized Rb atoms on coated Pyrex glass surfaces using edge enhancement

Kaifeng Zhao, Martin Schaden, Z. Wu

We present a method for measuring surface interaction parameters of spin-polarized Rb atoms on coated Pyrex glass surfaces based on edge enhancement in optically pumped Rb vapor. The best fit to the measured magnetic resonance lines using a theoretical model yields a dwell time ${\ensuremath{\tau}}_{s}=1.8\phantom{\rule{0.3em}{0ex}}\ensuremath{\mu}\mathrm{s}$ and a spin relaxation probability ${\ensuremath{\xi}}_{s}=0.015$ for a spin-polarized Rb atom on a Pyrex glass surface coated with dichlorooctamethyl-tetrasiloxane (Surfasil), and ${\ensuremath{\tau}}_{s}=0.5\phantom{\rule{0.3em}{0ex}}\ensuremath{\mu}\mathrm{s}$ and ${\ensuremath{\xi}}_{s}=0.001$ on a surface coated with octadecyltrichlorosilane (OTS).

Physical Review A•Sep 15, 2008•18 citations

Method for Measuring the Dwell Time of Spin-Polarized Rb Atoms on Coated Pyrex Glass Surfaces Using Light Shift

Kaifeng Zhao, Martin Schaden, Z. Wu

We present a simple method for directly measuring the average dwell time of spin-polarized Rb atoms on coated Pyrex glass surfaces. The method relies on the light shift of the Zeeman resonances of spin-polarized Rb atoms pumped and probed by evanescent waves, and does not depend on the microscopic details of surface interactions. We use a cell whose length is adjustable between 70 and $500\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$. The inverse of the difference between the frequency shifts caused by ${\ensuremath{\sigma}}^{+}$ and ${\ensuremath{\sigma}}^{\ensuremath{-}}$ pump beams depends linearly on the cell length, from which we obtain the average dwell time ${\ensuremath{\tau}}_{s}$. For a Pyrex glass cell coated with octadecyltrichlorosilane we find that ${\ensuremath{\tau}}_{s}=0.53\ifmmode\pm\else\textpm\fi{}0.03\text{ }\text{ }\ensuremath{\mu}\mathrm{s}$ at a cell wall temperature of $103\text{ }\ifmmode^\circ\else\textdegree\fi{}\mathrm{C}$. The temperature dependence of ${\ensuremath{\tau}}_{s}$ is fitted to ${\ensuremath{\tau}}_{s}={\overline{\ensuremath{\tau}}}_{0}\mathrm{exp}({E}_{a}/kT)$, yielding a preexponential factor ${\overline{\ensuremath{\tau}}}_{0}={2.2}_{\ensuremath{-}1.4}^{+5.1}\text{ }\text{ }\mathrm{ns}$ and an activation energy ${E}_{a}=0.19\ifmmode\pm\else\textpm\fi{}0.03\text{ }\text{ }\mathrm{eV}$.

Physical Review Letters•Aug 10, 2009•25 citations

Dwell Time Measurement of Wall Collisions of Spin Polarized Rb Atoms on Antirelaxation Coatings

Kaifeng Zhao, Emily Ulanski, Martin Schaden +1 more

Methods commonly used in surface science have difficulties in studying surface interaction between spin polarized atoms and anti-relaxation coatings in sealed atomic vapour cells. The average dwell time of atom-wall collisions can provide important information for understanding the atom surface interaction. Here we present a simple method for directly measuring the average dwell time of spin polarized rubidium atoms on coated glass surfaces. The method relies on evanescent-wave induced light shift of the Zeeman resonance of Rb atomic spins, and does not depend on the microscopic details of surface interactions. This is the only reliable method currently available for measuring surface dwell time of spin polarized atoms sealed in vapor cells.

Journal of Physics Conference Series•Nov 5, 2012•4 citations

Regionally specific hyperfine polarization of Rb atoms in the vicinity (∼10−5cm) of surfaces

Kaifeng Zhao, Zhan‐Chao Wu

We made regionally specific measurement of the hyperfine polarization $⟨\mathbit{S}∙\mathbit{I}⟩$ of Rb atoms in the vicinity $(\ensuremath{\sim}{10}^{\ensuremath{-}5}\phantom{\rule{0.3em}{0ex}}\mathrm{cm})$ of coated and uncoated Pyrex glass surfaces in optical pumping cells. This is in contrast to the previous hyperfine polarization studies, where the quantity measured is the bulk hyperfine polarization, which depends on surface interactions averaged over the entire cell surfaces. We probe the hyperfine polarization of the Rb atoms in the vicinity of cell surfaces using the evanescent wave of a weak laser beam. We find that the polarization in the vicinity of uncoated surfaces is significantly lower than that in the bulk. The polarization decreases rapidly with decreasing distance from the surface. By contrast, the polarization in the vicinity of a silicone-coated Pyrex glass surface is independent of the distance from the cell surface and is equal to the bulk polarization. Regionally specific measurement of the hyperfine polarization as a function of the penetration depth of the evanescent wave allows us to deduce the hyperfine polarization, its normal gradient, as well as the normal gradient coefficient ${\ensuremath{\mu}}_{\mathbit{S}∙\mathbit{I}}$ at the cell surface. We present the values of these quantities for three representative uncoated cells.

Physical Review A•Jan 19, 2005•16 citations

Hyperfine Polarization and Its Normal Gradient Coefficient of Rb87 Atoms in the Vicinity ( ∼10−5 cm ) of Coated and Uncoated Pyrex Glass Surfaces

Kaifeng Zhao, Z. Wu

We have made regionally specific measurement of the hyperfine polarization $⟨\mathbit{S}\ifmmode\cdot\else\textperiodcentered\fi{}\mathbit{I}⟩$ of $^{87}\mathrm{R}\mathrm{b}$ atoms in the vicinity ($\ensuremath{\sim}{10}^{\ensuremath{-}5}\text{ }\mathrm{c}\mathrm{m}$) of coated and uncoated Pyrex glass surfaces. We find that the polarization near an uncoated surface decreases rapidly with decreasing distance from the surface whereas for a silicone-coated surface the polarization is independent of the distance from the surface. We have also determined the normal gradient coefficient ${\ensuremath{\mu}}_{\mathbit{S}\ifmmode\cdot\else\textperiodcentered\fi{}\mathbit{I}}$ of the hyperfine polarization in uncoated cells. In a representative uncoated cell, at a Rb density $7.35\ifmmode\times\else\texttimes\fi{}{10}^{13}\text{ }{\mathrm{c}\mathrm{m}}^{\ensuremath{-}3}$ and a pump beam intensity $1.3\text{ }\mathrm{W}/{\mathrm{c}\mathrm{m}}^{2}$, we find ${\ensuremath{\mu}}_{\mathbit{S}\ifmmode\cdot\else\textperiodcentered\fi{}\mathbit{I}}=24\ifmmode\pm\else\textpm\fi{}7\text{ }\ensuremath{\mu}{\mathrm{m}}^{\ensuremath{-}1}$.

Physical Review Letters•Sep 10, 2003•10 citations

Interaction of spin-polarized atoms with a surface studied by optical-reflection spectroscopy

S. Grafström, Dieter Suter

We present an experiment for the investigation of the interaction of spin-polarized Na atoms with a dielectric surface. A laser beam, which is resonant with an atomic transition, probes the spin polarization near the surface. It is reflected at the surface and the change of its polarization is measured. Our analysis takes into account that the spin polarization is reduced near the surface because of surface-induced spin relaxation. The theory shows that strong wall relaxation leads to a clear modification of the shape and strength of the optical line. The dependence of the line shape on the angle of incidence immediately below the critical angle of total internal reflection provides a sensitive tool for the quantitative determination of the depolarization probability \ensuremath{\varepsilon} per wall collision. Measurements performed at a Pyrex glass surface provide a clear experimental confirmation of the theory and yield a value of \ensuremath{\varepsilon}\ensuremath{\approxeq}0.5. The case of weak wall relaxation is exemplified by experimental results from a silicone-coated glass surface, which are equally well reproduced by the theory. The method offers the prospect of using surface-induced spin relaxation for the study of surface properties and atom-surface interactions for various surfaces. \textcopyright{} 1996 The American Physical Society.

Physical Review A•Sep 1, 1996•17 citations
We present a detailed experimental and theoretical study of edge enhancement in optically pumped Rb vapor in coated cylindrical pyrex glass cells. The Zeeman polarization of Rb atoms is produced and probed in the vicinity (~$${10}^{\ensuremath{-}4} cm) of the cell surface by evanescent pump and probe beams. Spin-polarized Rb atoms diffuse throughout the cell in the presence of magnetic field gradients. In the present experiment the edge enhanced signal from the back surface of the cell is suppressed compared to that from the front surface, due to the fact that polarization is probed by the evanescent wave at the front surface only. The observed magnetic resonance line shape is reproduced quantitatively by a theoretical model and yields information about the dwell time and relaxation probability of Rb atoms on Pyrex glass surfaces coated with antirelaxation coatings.
We present a method for measuring surface interaction parameters of spin-polarized Rb atoms on coated Pyrex glass surfaces based on edge enhancement in optically pumped Rb vapor. The best fit to the measured magnetic resonance lines using a theoretical model yields a dwell time ${\ensuremath{\tau}}_{s}=1.8\phantom{\rule{0.3em}{0ex}}\ensuremath{\mu}\mathrm{s}$ and a spin relaxation probability ${\ensuremath{\xi}}_{s}=0.015$ for a spin-polarized Rb atom on a Pyrex glass surface coated with dichlorooctamethyl-tetrasiloxane (Surfasil), and ${\ensuremath{\tau}}_{s}=0.5\phantom{\rule{0.3em}{0ex}}\ensuremath{\mu}\mathrm{s}$ and ${\ensuremath{\xi}}_{s}=0.001$ on a surface coated with octadecyltrichlorosilane (OTS).
We present a simple method for directly measuring the average dwell time of spin-polarized Rb atoms on coated Pyrex glass surfaces. The method relies on the light shift of the Zeeman resonances of spin-polarized Rb atoms pumped and probed by evanescent waves, and does not depend on the microscopic details of surface interactions. We use a cell whose length is adjustable between 70 and $500\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$. The inverse of the difference between the frequency shifts caused by ${\ensuremath{\sigma}}^{+}$ and ${\ensuremath{\sigma}}^{\ensuremath{-}}$ pump beams depends linearly on the cell length, from which we obtain the average dwell time ${\ensuremath{\tau}}_{s}$. For a Pyrex glass cell coated with octadecyltrichlorosilane we find that ${\ensuremath{\tau}}_{s}=0.53\ifmmode\pm\else\textpm\fi{}0.03\text{ }\text{ }\ensuremath{\mu}\mathrm{s}$ at a cell wall temperature of $103\text{ }\ifmmode^\circ\else\textdegree\fi{}\mathrm{C}$. The temperature dependence of ${\ensuremath{\tau}}_{s}$ is fitted to ${\ensuremath{\tau}}_{s}={\overline{\ensuremath{\tau}}}_{0}\mathrm{exp}({E}_{a}/kT)$, yielding a preexponential factor ${\overline{\ensuremath{\tau}}}_{0}={2.2}_{\ensuremath{-}1.4}^{+5.1}\text{ }\text{ }\mathrm{ns}$ and an activation energy ${E}_{a}=0.19\ifmmode\pm\else\textpm\fi{}0.03\text{ }\text{ }\mathrm{eV}$.
Methods commonly used in surface science have difficulties in studying surface interaction between spin polarized atoms and anti-relaxation coatings in sealed atomic vapour cells. The average dwell time of atom-wall collisions can provide important information for understanding the atom surface interaction. Here we present a simple method for directly measuring the average dwell time of spin polarized rubidium atoms on coated glass surfaces. The method relies on evanescent-wave induced light shift of the Zeeman resonance of Rb atomic spins, and does not depend on the microscopic details of surface interactions. This is the only reliable method currently available for measuring surface dwell time of spin polarized atoms sealed in vapor cells.
We made regionally specific measurement of the hyperfine polarization $⟨\mathbit{S}∙\mathbit{I}⟩$ of Rb atoms in the vicinity $(\ensuremath{\sim}{10}^{\ensuremath{-}5}\phantom{\rule{0.3em}{0ex}}\mathrm{cm})$ of coated and uncoated Pyrex glass surfaces in optical pumping cells. This is in contrast to the previous hyperfine polarization studies, where the quantity measured is the bulk hyperfine polarization, which depends on surface interactions averaged over the entire cell surfaces. We probe the hyperfine polarization of the Rb atoms in the vicinity of cell surfaces using the evanescent wave of a weak laser beam. We find that the polarization in the vicinity of uncoated surfaces is significantly lower than that in the bulk. The polarization decreases rapidly with decreasing distance from the surface. By contrast, the polarization in the vicinity of a silicone-coated Pyrex glass surface is independent of the distance from the cell surface and is equal to the bulk polarization. Regionally specific measurement of the hyperfine polarization as a function of the penetration depth of the evanescent wave allows us to deduce the hyperfine polarization, its normal gradient, as well as the normal gradient coefficient ${\ensuremath{\mu}}_{\mathbit{S}∙\mathbit{I}}$ at the cell surface. We present the values of these quantities for three representative uncoated cells.
We have made regionally specific measurement of the hyperfine polarization $⟨\mathbit{S}\ifmmode\cdot\else\textperiodcentered\fi{}\mathbit{I}⟩$ of 87Rb^{87}\mathrm{R}\mathrm{b}87Rb atoms in the vicinity ($\ensuremath{\sim}{10}^{\ensuremath{-}5}\text{ }\mathrm{c}\mathrm{m}$) of coated and uncoated Pyrex glass surfaces. We find that the polarization near an uncoated surface decreases rapidly with decreasing distance from the surface whereas for a silicone-coated surface the polarization is independent of the distance from the surface. We have also determined the normal gradient coefficient ${\ensuremath{\mu}}_{\mathbit{S}\ifmmode\cdot\else\textperiodcentered\fi{}\mathbit{I}}$ of the hyperfine polarization in uncoated cells. In a representative uncoated cell, at a Rb density $7.35\ifmmode\times\else\texttimes\fi{}{10}^{13}\text{ }{\mathrm{c}\mathrm{m}}^{\ensuremath{-}3}$ and a pump beam intensity 1.3 W/cm21.3\text{ }\mathrm{W}/{\mathrm{c}\mathrm{m}}^{2}1.3 W/cm2, we find ${\ensuremath{\mu}}_{\mathbit{S}\ifmmode\cdot\else\textperiodcentered\fi{}\mathbit{I}}=24\ifmmode\pm\else\textpm\fi{}7\text{ }\ensuremath{\mu}{\mathrm{m}}^{\ensuremath{-}1}$.
We present an experiment for the investigation of the interaction of spin-polarized Na atoms with a dielectric surface. A laser beam, which is resonant with an atomic transition, probes the spin polarization near the surface. It is reflected at the surface and the change of its polarization is measured. Our analysis takes into account that the spin polarization is reduced near the surface because of surface-induced spin relaxation. The theory shows that strong wall relaxation leads to a clear modification of the shape and strength of the optical line. The dependence of the line shape on the angle of incidence immediately below the critical angle of total internal reflection provides a sensitive tool for the quantitative determination of the depolarization probability \ensuremath{\varepsilon} per wall collision. Measurements performed at a Pyrex glass surface provide a clear experimental confirmation of the theory and yield a value of \ensuremath{\varepsilon}\ensuremath{\approxeq}0.5. The case of weak wall relaxation is exemplified by experimental results from a silicone-coated glass surface, which are equally well reproduced by the theory. The method offers the prospect of using surface-induced spin relaxation for the study of surface properties and atom-surface interactions for various surfaces. \textcopyright{} 1996 The American Physical Society.