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 Letters

Spin Polarization of Rb and Cs np P232 ( n=5 , 6) Atoms by Circularly Polarized Photoexcitation of a Transient Diatomic Molecule

Andrey E. Mironov, J. Darby Hewitt, James Gary Eden

Published Mar 15, 2017• 8 citations
Publisher

Abstract

We report the selective population of Rb or Cs $np$ ${^{2}P}_{\frac{3}{2}}$ ($n=5$, 6; $F=4$, 5) hyperfine states by the photodissociation of a transient, alkali-rare gas diatomic molecule. Circularly polarized (${\ensuremath{\sigma}}^{\ensuremath{-}}$), amplified spontaneous emission (ASE) on the ${D}_{2}$ line of Rb or Cs (780.0 and 852.1 nm, respectively) is generated when Rb-Xe or Cs-Xe ground state collision pairs are photoexcited by a ${\ensuremath{\sigma}}^{+}$-polarized optical field having a wavelength within the ${D}_{2}$ blue satellite continuum, associated with the $B{^{2}\mathrm{\ensuremath{\Sigma}}}_{\frac{1}{2}}^{+}\ensuremath{\leftarrow}X{^{2}\mathrm{\ensuremath{\Sigma}}}_{\frac{1}{2}}^{+}$ ($\text{free}\ensuremath{\leftarrow}\text{free}$) transition of the diatomic molecule. The degree of spin polarization of Cs ($6p$ $^{2}{P}_{\frac{3}{2}}$), specifically, is found to be dependent on the interatomic distance ($R$) at which the excited complex is born, a result attributed to the structure of the $B{^{2}\mathrm{\ensuremath{\Sigma}}}_{\frac{1}{2}}^{+}$ state. For Cs-Xe atomic pairs, tuning the wavelength of the optical field from 843 to 848 nm varies the degree of circular polarization of the ASE from 63% to almost unity because of the perturbation, in the $5\ensuremath{\le}R\ensuremath{\le}6\text{ }\text{ }\AA{}$ interval, of the ${^{2}\mathrm{\ensuremath{\Sigma}}}_{\frac{1}{2}}^{+}$ potential by a $d\ensuremath{\sigma}$ molecular orbital associated with a higher $^{2}\mathrm{\ensuremath{\Lambda}}$ electronic state. Monitoring only the Cs $6p$ $^{2}{P}_{\frac{3}{2}}$ spin polarization reveals a previously unobserved interaction of CsXe ($B{^{2}\mathrm{\ensuremath{\Sigma}}}_{\frac{1}{2}}^{+}$) with the lowest vibrational levels of a $^{2}\mathrm{\ensuremath{\Lambda}}$ state derived from Cs $(5d)+\mathrm{Xe}$. By inserting a molecular intermediate into the alkali atom excitation mechanism, these experiments realize electronic spin polarization through populating no more than two $np$ ${^{2}P}_{\frac{3}{2}}$ hyperfine states, and demonstrate a sensitive spectroscopic probe of $R$-dependent state-state interactions and their impact on interatomic potentials.

DOI
10.1103/physrevlett.118.113201

Related papers

Manipulating excited state hyperfine level populations in an atomic laser through electronic spin polarization: controlling upper laser level degeneracy and small signal gain

Andrey E. Mironov, James Gary Eden

Anisotropic coherent radiation has been generated from an isotropic medium, in the absence of an external magnetic field, by the spin polarization of an atomic excited state. Lasing on specific hyperfine lines of the 6p2P32→6s2S12 (D2) transition of Cs at 852.1 nm has been realized by photoexciting Cs-rare gas thermal collision pairs with a circularly-polarized (σ+) optical field. Subsequent dissociation of the transient Cs-rare gas B2Σ12+ diatomic molecule selectively populates theF= 4, 5 hyperfine levels of the Cs 6p2P32 state. Not only does electronic spin polarization of the upper laser level yield circularly-polarized coherent emission, but the effective degeneracy (g2) of the 6p2P32 state is altered by the non-statistical hyperfine state population distribution, thereby permitting control of the laser small signal gain with an elliptically-polarized pump optical field. TheD2laser efficiency and output power correlate directly with the molecular orbital structure of the Cs-rare gasB2Σ+state in the region of internuclear separation at which the diatomic complex is born.

Optics Express•Jan 1, 2017•4 citations

Laser-enhanced spin-exchange collisions

Linda L. Vahala, Mark D. Havey

Spin‐exchange collisions between optically pumped alkali atoms and rare gas atoms can polarize the nuclei of rare gas atoms. We present calculations which indicate that the process should be readily modified by relatively weak (<1 KW/cm2) CW laser radiation tuned in the vicinity of the Rb‐rare gas 5sΣ−6sΣ free‐bound molecular transition. Full coupling of the spin‐polarized Rb electronic spin to the rare gas nuclear spin in the excited state lifetime leads to an estimate for Rb–Xe of a cross section σ≂10−22 Pcm2, where P is the laser power in KW/cm2.

AIP conference proceedings•Jan 1, 1986•0 citations

Photodissociation of RbI at 266 nm: spin orientation of ground state Rb atoms

Dmitriy V. Kupriyanov, B. V. Picheyev, S Vasyutinskii

A study has been made on the oriented ground state 5 2 S 1/2 Rb atoms produced in molecular photodissociation. Low-pressure RbI vapours have been photolysed by a beam of circularly polarized impulse laser radiation at 266 nm. The resulting Rb atoms were probed by a resonance atomic line at 794.8 nm from a discharge Rb lamp in two different experimental geometries. A free precession of the oriented atomic spins in an external magnetic field was detected by a dichroism of the atomic vapours. The initial degree of spin orientation was found to be P c = (20 +or- 2)%.

Journal of Physics B Atomic Molecular and Optical Physics•Dec 14, 1993•7 citations

Polarization spectra of excited-state-Mg(3p)–rare-gas-atom optical collisions

Rosemary A. Lasell, D. A. Olsgaard, Mark D. Havey +1 more

Experimental, polarization-dependent excitation spectra for excited-state-Mg--rare-gas-atom optical collisions are reported. In these first studies of the process, polarized Mg atoms in the 3p $^{1}$${\mathit{P}}_{1}$ level are produced by absorption of linearly polarized light tuned to the 3s $^{1}$${\mathit{S}}_{0}$\ensuremath{\rightarrow}3p $^{1}$${\mathit{P}}_{1}$ resonance transition at 285.2 nm. Detuning-dependent, collision-induced polarization spectra are measured in a \ifmmode\pm\else\textpm\fi{}200-${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ range around the Mg 3p $^{1}$${\mathit{P}}_{1}$\ensuremath{\rightarrow}5s $^{1}$${\mathit{S}}_{0}$ transition at 571.2 nm. The spectra correspond to probing transient Mg-Ne and Mg-Ar molecules on 3p $^{1}\mathrm{\ensuremath{\Pi}}_{1}$\ensuremath{\rightarrow}5s $^{1}\mathrm{\ensuremath{\Sigma}}_{0}^{+}$ and 3p $^{1}\mathrm{\ensuremath{\Sigma}}_{0}^{+}$\ensuremath{\rightarrow}5s $^{1}\mathrm{\ensuremath{\Sigma}}_{0}^{+}$ electronic transitions. Measurements of these excited-state polarization spectra for Mg-Ne optical collisions reveal that for detunings to the red of the atomic Mg 3p $^{1}$${\mathit{P}}_{1}$\ensuremath{\rightarrow}5s $^{1}$${\mathit{S}}_{0}$ transition, electronic linear polarization greater than 50% survives far into the molecular regime. This represents a direct measure of the polarization important to alignment-dependent inelastic processes in alkaline-earth-metal--rare-gas-atom collisions. The polarization spectra are discussed in terms of existing information on the interatomic potentials and through an axial recoil limit for the polarization degree for parallel and perpendicular molecular transitions. Rate coefficients k for disalignment of Mg 3p $^{1}$${\mathit{P}}_{1}$ atoms by collisions with Ar [k=9.4(5)\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}10}$ ${\mathrm{cm}}^{3}$/s] and with Ne [k=6.5(7)\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}10}$ ${\mathrm{cm}}^{3}$/s] are also extracted from the data.

Physical Review A•Jul 1, 1994•9 citations

Level structure of deeply bound levels of the c3Σg+ state of Rb287

Björn Drews, Markus Deiß, Joschka Wolf +2 more

We spectroscopically investigate the hyperfine, rotational, and Zeeman structure of the vibrational levels ${v}^{\ensuremath{'}}=0,7,13$ within the electronically excited $c{\phantom{\rule{0.222222em}{0ex}}}^{3}{\mathrm{\ensuremath{\Sigma}}}_{g}{}^{+}$ state of $^{87}\mathrm{Rb}_{2}$ for magnetic fields of up to $1000\phantom{\rule{0.28em}{0ex}}\text{G}$. As spectroscopic methods we use short-range photoassociation of ultracold Rb atoms as well as photoexcitation of ultracold molecules which have been previously prepared in several well-defined quantum states of the $a{\phantom{\rule{0.222222em}{0ex}}}^{3}\mathrm{\ensuremath{\Sigma}}{}_{u}^{+}$ potential. As a by-product, we present optical two-photon transfer of weakly bound Feshbach molecules into $a{\phantom{\rule{0.222222em}{0ex}}}^{3}\mathrm{\ensuremath{\Sigma}}{}_{u}^{+}$, $v=0$ levels featuring different nuclear spin quantum numbers. A simple model reproduces well the molecular level structures of the $c{\phantom{\rule{0.222222em}{0ex}}}^{3}{\mathrm{\ensuremath{\Sigma}}}_{g}{}^{+}$ vibrational states and provides a consistent assignment of the measured resonance lines. Furthermore, the model can be used to predict the relative transition strengths of the lines. From fits to the data we extract for each vibrational level the rotational constant, the effective spin-spin interaction constant, as well as the Fermi contact parameter and the anisotropic hyperfine constant. In an alternative approach, we perform coupled-channel calculations where we fit the relevant potential energy curves, spin-orbit interactions, and hyperfine functions. The calculations reproduce the measured hyperfine level term frequencies with an average uncertainty of $\ifmmode\pm\else\textpm\fi{}9\phantom{\rule{0.28em}{0ex}}\mathrm{MHz}$, similar as for the simple model. From these fits we obtain a section of the potential energy curve for the $c{\phantom{\rule{0.222222em}{0ex}}}^{3}{\mathrm{\ensuremath{\Sigma}}}_{g}{}^{+}$ state which can be used for predicting the level structure for the vibrational manifold ${v}^{\ensuremath{'}}=0$ to 13 of this electronic state.

arXiv:1703.07752•Physical Review A•Jun 23, 2017•5 citations

LASER SPECTROSCOPY OF THE PHOTOASSOCIATION OF Rb-Ar AND Rb-Kr THERMAL PAIRS: STRUCTURE OF THE Rb-RARE GAS A2_1/2 STATE NEAR THE CLASSICAL LIMIT

William Goldshlag

A new laser spectroscopic technique has been demonstrated for examining the structure of alkali--rare gas diatomic electronic states near the classical limit. In two-color experiments, Rb--Ar or Rb--Kr thermal pairs are excited by free$leftarrow$free or bound$leftarrow$free transitions while monitoring the amplified spontaneous emission produced on the Rb D$_1$ or D$_2$ lines. Spectra observed lying within 10 cm$^{-1}$ of the separated atom limit for the A$^{2}Pi_{1/2}$ states of Rb--Ar and Rb--Kr will be presented and discussed.

•Jan 5, 2016•0 citations
We report the selective population of Rb or Cs npnpnp 2P32{^{2}P}_{\frac{3}{2}}2P23​​ (n=5n=5n=5, 6; F=4F=4F=4, 5) hyperfine states by the photodissociation of a transient, alkali-rare gas diatomic molecule. Circularly polarized (\ensuremathσ\ensuremath−{\ensuremath{\sigma}}^{\ensuremath{-}}\ensuremathσ\ensuremath−), amplified spontaneous emission (ASE) on the D2{D}_{2}D2​ line of Rb or Cs (780.0 and 852.1 nm, respectively) is generated when Rb-Xe or Cs-Xe ground state collision pairs are photoexcited by a \ensuremathσ+{\ensuremath{\sigma}}^{+}\ensuremathσ+-polarized optical field having a wavelength within the D2{D}_{2}D2​ blue satellite continuum, associated with the B2\ensuremathΣ12+\ensuremath←X2\ensuremathΣ12+B{^{2}\mathrm{\ensuremath{\Sigma}}}_{\frac{1}{2}}^{+}\ensuremath{\leftarrow}X{^{2}\mathrm{\ensuremath{\Sigma}}}_{\frac{1}{2}}^{+}B2\ensuremathΣ21​+​\ensuremath←X2\ensuremathΣ21​+​ (free\ensuremath←free\text{free}\ensuremath{\leftarrow}\text{free}free\ensuremath←free) transition of the diatomic molecule. The degree of spin polarization of Cs (6p6p6p 2P32^{2}{P}_{\frac{3}{2}}2P23​​), specifically, is found to be dependent on the interatomic distance (RRR) at which the excited complex is born, a result attributed to the structure of the B2\ensuremathΣ12+B{^{2}\mathrm{\ensuremath{\Sigma}}}_{\frac{1}{2}}^{+}B2\ensuremathΣ21​+​ state. For Cs-Xe atomic pairs, tuning the wavelength of the optical field from 843 to 848 nm varies the degree of circular polarization of the ASE from 63% to almost unity because of the perturbation, in the 5\ensuremath≤R\ensuremath≤6  A˚5\ensuremath{\le}R\ensuremath{\le}6\text{ }\text{ }\AA{}5\ensuremath≤R\ensuremath≤6  A˚ interval, of the 2\ensuremathΣ12+{^{2}\mathrm{\ensuremath{\Sigma}}}_{\frac{1}{2}}^{+}2\ensuremathΣ21​+​ potential by a d\ensuremathσd\ensuremath{\sigma}d\ensuremathσ molecular orbital associated with a higher 2\ensuremathΛ^{2}\mathrm{\ensuremath{\Lambda}}2\ensuremathΛ electronic state. Monitoring only the Cs 6p6p6p 2P32^{2}{P}_{\frac{3}{2}}2P23​​ spin polarization reveals a previously unobserved interaction of CsXe (B2\ensuremathΣ12+B{^{2}\mathrm{\ensuremath{\Sigma}}}_{\frac{1}{2}}^{+}B2\ensuremathΣ21​+​) with the lowest vibrational levels of a 2\ensuremathΛ^{2}\mathrm{\ensuremath{\Lambda}}2\ensuremathΛ state derived from Cs (5d)+Xe(5d)+\mathrm{Xe}(5d)+Xe. By inserting a molecular intermediate into the alkali atom excitation mechanism, these experiments realize electronic spin polarization through populating no more than two npnpnp 2P32{^{2}P}_{\frac{3}{2}}2P23​​ hyperfine states, and demonstrate a sensitive spectroscopic probe of RRR-dependent state-state interactions and their impact on interatomic potentials.
Anisotropic coherent radiation has been generated from an isotropic medium, in the absence of an external magnetic field, by the spin polarization of an atomic excited state. Lasing on specific hyperfine lines of the 6p2P32→6s2S12 (D2) transition of Cs at 852.1 nm has been realized by photoexciting Cs-rare gas thermal collision pairs with a circularly-polarized (σ+) optical field. Subsequent dissociation of the transient Cs-rare gas B2Σ12+ diatomic molecule selectively populates theF= 4, 5 hyperfine levels of the Cs 6p2P32 state. Not only does electronic spin polarization of the upper laser level yield circularly-polarized coherent emission, but the effective degeneracy (g2) of the 6p2P32 state is altered by the non-statistical hyperfine state population distribution, thereby permitting control of the laser small signal gain with an elliptically-polarized pump optical field. TheD2laser efficiency and output power correlate directly with the molecular orbital structure of the Cs-rare gasB2Σ+state in the region of internuclear separation at which the diatomic complex is born.
Spin‐exchange collisions between optically pumped alkali atoms and rare gas atoms can polarize the nuclei of rare gas atoms. We present calculations which indicate that the process should be readily modified by relatively weak (<1 KW/cm2) CW laser radiation tuned in the vicinity of the Rb‐rare gas 5sΣ−6sΣ free‐bound molecular transition. Full coupling of the spin‐polarized Rb electronic spin to the rare gas nuclear spin in the excited state lifetime leads to an estimate for Rb–Xe of a cross section σ≂10−22 Pcm2, where P is the laser power in KW/cm2.
A study has been made on the oriented ground state 5 2 S 1/2 Rb atoms produced in molecular photodissociation. Low-pressure RbI vapours have been photolysed by a beam of circularly polarized impulse laser radiation at 266 nm. The resulting Rb atoms were probed by a resonance atomic line at 794.8 nm from a discharge Rb lamp in two different experimental geometries. A free precession of the oriented atomic spins in an external magnetic field was detected by a dichroism of the atomic vapours. The initial degree of spin orientation was found to be P c = (20 +or- 2)%.
Experimental, polarization-dependent excitation spectra for excited-state-Mg--rare-gas-atom optical collisions are reported. In these first studies of the process, polarized Mg atoms in the 3p 1^{1}1P1{\mathit{P}}_{1}P1​ level are produced by absorption of linearly polarized light tuned to the 3s 1^{1}1S0{\mathit{S}}_{0}S0​\ensuremath{\rightarrow}3p 1^{1}1P1{\mathit{P}}_{1}P1​ resonance transition at 285.2 nm. Detuning-dependent, collision-induced polarization spectra are measured in a \ifmmode\pm\else\textpm\fi{}200-${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ range around the Mg 3p 1^{1}1P1{\mathit{P}}_{1}P1​\ensuremath{\rightarrow}5s 1^{1}1S0{\mathit{S}}_{0}S0​ transition at 571.2 nm. The spectra correspond to probing transient Mg-Ne and Mg-Ar molecules on 3p $^{1}\mathrm{\ensuremath{\Pi}}_{1}$\ensuremath{\rightarrow}5s $^{1}\mathrm{\ensuremath{\Sigma}}_{0}^{+}$ and 3p $^{1}\mathrm{\ensuremath{\Sigma}}_{0}^{+}$\ensuremath{\rightarrow}5s $^{1}\mathrm{\ensuremath{\Sigma}}_{0}^{+}$ electronic transitions. Measurements of these excited-state polarization spectra for Mg-Ne optical collisions reveal that for detunings to the red of the atomic Mg 3p 1^{1}1P1{\mathit{P}}_{1}P1​\ensuremath{\rightarrow}5s 1^{1}1S0{\mathit{S}}_{0}S0​ transition, electronic linear polarization greater than 50% survives far into the molecular regime. This represents a direct measure of the polarization important to alignment-dependent inelastic processes in alkaline-earth-metal--rare-gas-atom collisions. The polarization spectra are discussed in terms of existing information on the interatomic potentials and through an axial recoil limit for the polarization degree for parallel and perpendicular molecular transitions. Rate coefficients k for disalignment of Mg 3p 1^{1}1P1{\mathit{P}}_{1}P1​ atoms by collisions with Ar [k=9.4(5)\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}10}$ cm3{\mathrm{cm}}^{3}cm3/s] and with Ne [k=6.5(7)\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}10}$ cm3{\mathrm{cm}}^{3}cm3/s] are also extracted from the data.
We spectroscopically investigate the hyperfine, rotational, and Zeeman structure of the vibrational levels ${v}^{\ensuremath{'}}=0,7,13$ within the electronically excited $c{\phantom{\rule{0.222222em}{0ex}}}^{3}{\mathrm{\ensuremath{\Sigma}}}_{g}{}^{+}$ state of 87Rb2^{87}\mathrm{Rb}_{2}87Rb2​ for magnetic fields of up to 1000G1000\phantom{\rule{0.28em}{0ex}}\text{G}1000G. As spectroscopic methods we use short-range photoassociation of ultracold Rb atoms as well as photoexcitation of ultracold molecules which have been previously prepared in several well-defined quantum states of the $a{\phantom{\rule{0.222222em}{0ex}}}^{3}\mathrm{\ensuremath{\Sigma}}{}_{u}^{+}$ potential. As a by-product, we present optical two-photon transfer of weakly bound Feshbach molecules into $a{\phantom{\rule{0.222222em}{0ex}}}^{3}\mathrm{\ensuremath{\Sigma}}{}_{u}^{+}$, v=0v=0v=0 levels featuring different nuclear spin quantum numbers. A simple model reproduces well the molecular level structures of the $c{\phantom{\rule{0.222222em}{0ex}}}^{3}{\mathrm{\ensuremath{\Sigma}}}_{g}{}^{+}$ vibrational states and provides a consistent assignment of the measured resonance lines. Furthermore, the model can be used to predict the relative transition strengths of the lines. From fits to the data we extract for each vibrational level the rotational constant, the effective spin-spin interaction constant, as well as the Fermi contact parameter and the anisotropic hyperfine constant. In an alternative approach, we perform coupled-channel calculations where we fit the relevant potential energy curves, spin-orbit interactions, and hyperfine functions. The calculations reproduce the measured hyperfine level term frequencies with an average uncertainty of $\ifmmode\pm\else\textpm\fi{}9\phantom{\rule{0.28em}{0ex}}\mathrm{MHz}$, similar as for the simple model. From these fits we obtain a section of the potential energy curve for the $c{\phantom{\rule{0.222222em}{0ex}}}^{3}{\mathrm{\ensuremath{\Sigma}}}_{g}{}^{+}$ state which can be used for predicting the level structure for the vibrational manifold ${v}^{\ensuremath{'}}=0$ to 13 of this electronic state.
A new laser spectroscopic technique has been demonstrated for examining the structure of alkali--rare gas diatomic electronic states near the classical limit. In two-color experiments, Rb--Ar or Rb--Kr thermal pairs are excited by freeleftarrowleftarrowleftarrowfree or boundleftarrowleftarrowleftarrowfree transitions while monitoring the amplified spontaneous emission produced on the Rb D1_11​ or D2_22​ lines. Spectra observed lying within 10 cm−1^{-1}−1 of the separated atom limit for the A2Pi1/2^{2}Pi_{1/2}2Pi1/2​ states of Rb--Ar and Rb--Kr will be presented and discussed.