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

Probing the alignment of ultracold spin-polarized $\textrm{Rb}_2$ molecules

Markus Deiß, Björn Drews, Benjamin Deissler, Johannes Hecker Denschlag

Published Apr 4, 2014• 0 citations
OpenAlex

Abstract

We demonstrate a method to probe the alignment of the molecular axis of spin-polarized ultracold dimers. Diatomic $^{87}$Rb$_2$ molecules are held in the lowest Bloch band of a far-off resonance 3D optical lattice. Using lattice modulation spectroscopy we measure the molecular polarizabilities, which are directly linked to the alignment, along each of the $x$-, $y$-, and $z$-directions of the lab coordinate system. In contrast to nonrotating molecules, we observe that rotating molecules have an anisotropic orientation of the molecular axis. Furthermore, we derive the dynamical polarizabilities for a laser wavelength of 1064.5 nm parallel and orthogonal to the molecular axis of the dimer, $\alpha_\parallel=(8.9 \pm 0.9)\times10^3\:\textrm{a.u.}$ and $\alpha_\perp=(0.9 \pm 0.4)\times10^3\:\textrm{a.u.}$, respectively.

Related papers

Probing the Axis Alignment of an Ultracold Spin-polarized Rb2 Molecule

Markus Deiß, Björn Drews, Benjamin Deissler +1 more

We present a novel method for probing the alignment of the molecular axis of an ultracold, nonpolar dimer. These results are obtained using diatomic ^{87}Rb_{2} molecules in the vibrational ground state of the lowest triplet potential a^{3}Σ_{u}^{+} trapped in a 3D optical lattice. We measure the molecular polarizabilities, which are directly linked to the alignment, along each of the x, y, and z directions of the lab coordinate system. By preparing the molecules in various, precisely defined rotational quantum states we can control the degree of alignment of the molecular axis with high precision over a large range. Furthermore, we derive the dynamical polarizabilities for a laser wavelength of 1064.5 nm parallel and orthogonal to the molecular axis of the dimer, α_{∥}=(8.9±0.9)×10^{3} a.u. and α_{⊥}=(0.9±0.4)×10^{3} a.u., respectively. Our findings highlight that the depth of an optical lattice strongly depends on the rotational state of the molecule, which has to be considered in collision experiments. The present work paves the way for reaction studies between aligned molecules in the ultracold temperature regime.

arXiv:1404.1255•Physical Review Letters•Dec 3, 2014•20 citations

Polarizability of ultracold molecules in the rovibrational ground state of

Markus Deiß, Björn Drews, Johannes Hecker Denschlag +3 more

Abstract We study, both theoretically and experimentally, the dynamical polarizability of molecules in the rovibrational ground state of . Taking all relevant excited molecular bound states into account, we compute the complex-valued polarizability for wave numbers up to 20 000 . Our calculations are compared to experimental results at ( ) as well as at ( ). Here, we discuss the measurements at . The ultracold Rb2 molecules are trapped in the lowest Bloch band of a 3D optical lattice. Their polarizability is determined by lattice modulation spectroscopy which measures the potential depth for a given light intensity. Moreover, we investigate the decay of molecules in the optical lattice, where lifetimes of more than are observed. In addition, the dynamical polarizability for the state is calculated. We provide simple analytical expressions that reproduce the numerical results for for all vibrational levels of as well as . Precise knowledge of the molecular polarizability is essential for designing experiments with ultracold molecules as lifetimes and lattice depths are key parameters. Specifically the wavelength at is of interest, since here, ultrastable high power lasers are available.

arXiv:1501.03793•New Journal of Physics•Jun 1, 2015•15 citations

Anisotropic Polarizability of Ultracold Polar K 40 Rb 87 Molecules

Brian Neyenhuis, Bo Yan, Steven A. Moses +6 more

We report the measurement of the anisotropic ac polarizability of ultracold polar (40)K(87)Rb molecules in the ground and first rotationally excited states. Theoretical analysis of the polarizability agrees well with experimental findings. Although the polarizability can vary by more than 30%, a "magic" angle between the laser polarization and the quantization axis is found where the polarizability of the |N=0,m(N)=0> and the |N=1,m(N)=0> states match. At this angle, rotational decoherence due to the mismatch in trapping potentials is eliminated, and we observe a sharp increase in the coherence time. This paves the way for precise spectroscopic measurements and coherent manipulations of rotational states as a tool in the creation and probing of novel quantum many-body states of polar molecules.

arXiv:1209.2226•Physical Review Letters•Dec 4, 2012•100 citations

Polarizability of ultracold Rb2 molecules in the rovibrational ground state of a3Σ+u

Nadia Bouloufa-Maafa, Olivier Dulieu, Romain Véxiau +3 more

We study, both theoretically and experimentally, the dynamical polarizability α(ω) of Rb2 molecules in the rovibrational ground state of a3Σ+u. Taking all relevant excited molecular bound states into account, we compute the complex-valued polarizability α(ω) for wave numbers up to 20000cm−1. Our calculations are compared to experimental results at 1064.5nm (∼9400cm−1) as well as at 830.4nm (∼12000cm−1). Here, we discuss the measurements at 1064.5nm. The ultracold Rb2 molecules are trapped in the lowest Bloch band of a 3D optical lattice. Their polarizability is determined by lattice modulation spectroscopy which measures the potential depth for a given light intensity. Moreover, we investigate the decay of molecules in the optical lattice, where lifetimes of more than 2s are observed. In addition, the dynamical polarizability for the X1Σ+g state is calculated. We provide simple analytical expressions that reproduce the numerical results for α(ω) for all vibrational levels of a3Σ+u as well as X1Σ+g. Precise knowledge of the molecular polarizability is essential for designing experiments with ultracold molecules as lifetimes and lattice depths are key parameters. Specifically the wavelength at ∼1064nm is of interest, since here, ultrastable high power lasers are available.

•Jan 19, 2015•0 citations

Calculations of static dipole polarizabilities of alkali dimers: Prospects for alignment of ultracold molecules

Johannes Deiglmayr, M Aymar, Roland Wester +2 more

The rapid development of experimental techniques to produce ultracold alkali molecules opens the ways to manipulate them and to control their dynamics using external electric fields. A prerequisite quantity for such studies is the knowledge of their static dipole polarizability. In this paper, we computed the variations with internuclear distance and with vibrational index of the static dipole polarizability components of all homonuclear alkali dimers including Fr(2), and of all heteronuclear alkali dimers involving Li to Cs, in their electronic ground state and in their lowest triplet state. We use the same quantum chemistry approach as in our work on dipole moments [Aymar and Dulieu, J. Chem. Phys. 122, 204302 (2005)], based on pseudopotentials for atomic core representation, Gaussian basis sets, and effective potentials for core polarization. Polarizabilities are extracted from electronic energies using the finite-field method. For the heaviest species Rb(2), Cs(2), and Fr(2) and for all heteronuclear alkali dimers, such results are presented for the first time. The accuracy of our results on atomic and molecular static dipole polarizabilities is discussed by comparing our values with the few available experimental data and elaborate calculations. We found that for all alkali pairs, the parallel and perpendicular components of the ground state polarizabilities at the equilibrium distance R(e) scale as (R(e))(3), which can be related to a simple electrostatic model of an ellipsoidal charge distribution. Prospects for possible alignment and orientation effects with these molecules in forthcoming experiments are discussed.

arXiv:0807.3301•The Journal of Chemical Physics•Aug 12, 2008•148 citations

Anisotropic polarizability of ultracold ground-state Na 23 Rb 87 molecules

Junyu Lin, J. He, Xin Ye +1 more

We report measurements of the AC polarizabilities of ultracold ground-state $^{23}\mathrm{Na}^{87}\mathrm{Rb}$ molecules. While the polarizability of the ground rotational state $J=0$ is isotropic, that of the first excited rotational state $J=1$ is anisotropic and depends strongly on the light polarization angle. We obtain both polarizabilities precisely by combining trap oscillation frequency measurement and high-resolution rotational spectroscopy driven by microwave. With the optimized light polarization angle and intensity combination, the nonuniformity of the differential AC Stark shift between the two rotational states is minimized and the rotational coherence time is observed to be the longest.

arXiv:2012.11093•Physical Review A•Feb 25, 2021•9 citations
Probing the alignment of ultracold spin-polarized Rb2\textrm{Rb}_2Rb2​ molecules
We demonstrate a method to probe the alignment of the molecular axis of spin-polarized ultracold dimers. Diatomic 87^{87}87Rb2_22​ molecules are held in the lowest Bloch band of a far-off resonance 3D optical lattice. Using lattice modulation spectroscopy we measure the molecular polarizabilities, which are directly linked to the alignment, along each of the xxx-, yyy-, and zzz-directions of the lab coordinate system. In contrast to nonrotating molecules, we observe that rotating molecules have an anisotropic orientation of the molecular axis. Furthermore, we derive the dynamical polarizabilities for a laser wavelength of 1064.5 nm parallel and orthogonal to the molecular axis of the dimer, α∥=(8.9±0.9)×103 a.u.\alpha_\parallel=(8.9 \pm 0.9)\times10^3\:\textrm{a.u.}α∥​=(8.9±0.9)×103a.u. and α⊥=(0.9±0.4)×103 a.u.\alpha_\perp=(0.9 \pm 0.4)\times10^3\:\textrm{a.u.}α⊥​=(0.9±0.4)×103a.u., respectively.
We present a novel method for probing the alignment of the molecular axis of an ultracold, nonpolar dimer. These results are obtained using diatomic ^{87}Rb_{2} molecules in the vibrational ground state of the lowest triplet potential a^{3}Σ_{u}^{+} trapped in a 3D optical lattice. We measure the molecular polarizabilities, which are directly linked to the alignment, along each of the x, y, and z directions of the lab coordinate system. By preparing the molecules in various, precisely defined rotational quantum states we can control the degree of alignment of the molecular axis with high precision over a large range. Furthermore, we derive the dynamical polarizabilities for a laser wavelength of 1064.5 nm parallel and orthogonal to the molecular axis of the dimer, α_{∥}=(8.9±0.9)×10^{3} a.u. and α_{⊥}=(0.9±0.4)×10^{3} a.u., respectively. Our findings highlight that the depth of an optical lattice strongly depends on the rotational state of the molecule, which has to be considered in collision experiments. The present work paves the way for reaction studies between aligned molecules in the ultracold temperature regime.
Abstract We study, both theoretically and experimentally, the dynamical polarizability of molecules in the rovibrational ground state of . Taking all relevant excited molecular bound states into account, we compute the complex-valued polarizability for wave numbers up to 20 000 . Our calculations are compared to experimental results at ( ) as well as at ( ). Here, we discuss the measurements at . The ultracold Rb2 molecules are trapped in the lowest Bloch band of a 3D optical lattice. Their polarizability is determined by lattice modulation spectroscopy which measures the potential depth for a given light intensity. Moreover, we investigate the decay of molecules in the optical lattice, where lifetimes of more than are observed. In addition, the dynamical polarizability for the state is calculated. We provide simple analytical expressions that reproduce the numerical results for for all vibrational levels of as well as . Precise knowledge of the molecular polarizability is essential for designing experiments with ultracold molecules as lifetimes and lattice depths are key parameters. Specifically the wavelength at is of interest, since here, ultrastable high power lasers are available.
We report the measurement of the anisotropic ac polarizability of ultracold polar (40)K(87)Rb molecules in the ground and first rotationally excited states. Theoretical analysis of the polarizability agrees well with experimental findings. Although the polarizability can vary by more than 30%, a "magic" angle between the laser polarization and the quantization axis is found where the polarizability of the |N=0,m(N)=0> and the |N=1,m(N)=0> states match. At this angle, rotational decoherence due to the mismatch in trapping potentials is eliminated, and we observe a sharp increase in the coherence time. This paves the way for precise spectroscopic measurements and coherent manipulations of rotational states as a tool in the creation and probing of novel quantum many-body states of polar molecules.
We study, both theoretically and experimentally, the dynamical polarizability α(ω) of Rb2 molecules in the rovibrational ground state of a3Σ+u. Taking all relevant excited molecular bound states into account, we compute the complex-valued polarizability α(ω) for wave numbers up to 20000cm−1. Our calculations are compared to experimental results at 1064.5nm (∼9400cm−1) as well as at 830.4nm (∼12000cm−1). Here, we discuss the measurements at 1064.5nm. The ultracold Rb2 molecules are trapped in the lowest Bloch band of a 3D optical lattice. Their polarizability is determined by lattice modulation spectroscopy which measures the potential depth for a given light intensity. Moreover, we investigate the decay of molecules in the optical lattice, where lifetimes of more than 2s are observed. In addition, the dynamical polarizability for the X1Σ+g state is calculated. We provide simple analytical expressions that reproduce the numerical results for α(ω) for all vibrational levels of a3Σ+u as well as X1Σ+g. Precise knowledge of the molecular polarizability is essential for designing experiments with ultracold molecules as lifetimes and lattice depths are key parameters. Specifically the wavelength at ∼1064nm is of interest, since here, ultrastable high power lasers are available.
The rapid development of experimental techniques to produce ultracold alkali molecules opens the ways to manipulate them and to control their dynamics using external electric fields. A prerequisite quantity for such studies is the knowledge of their static dipole polarizability. In this paper, we computed the variations with internuclear distance and with vibrational index of the static dipole polarizability components of all homonuclear alkali dimers including Fr(2), and of all heteronuclear alkali dimers involving Li to Cs, in their electronic ground state and in their lowest triplet state. We use the same quantum chemistry approach as in our work on dipole moments [Aymar and Dulieu, J. Chem. Phys. 122, 204302 (2005)], based on pseudopotentials for atomic core representation, Gaussian basis sets, and effective potentials for core polarization. Polarizabilities are extracted from electronic energies using the finite-field method. For the heaviest species Rb(2), Cs(2), and Fr(2) and for all heteronuclear alkali dimers, such results are presented for the first time. The accuracy of our results on atomic and molecular static dipole polarizabilities is discussed by comparing our values with the few available experimental data and elaborate calculations. We found that for all alkali pairs, the parallel and perpendicular components of the ground state polarizabilities at the equilibrium distance R(e) scale as (R(e))(3), which can be related to a simple electrostatic model of an ellipsoidal charge distribution. Prospects for possible alignment and orientation effects with these molecules in forthcoming experiments are discussed.
We report measurements of the AC polarizabilities of ultracold ground-state 23Na87Rb^{23}\mathrm{Na}^{87}\mathrm{Rb}23Na87Rb molecules. While the polarizability of the ground rotational state J=0J=0J=0 is isotropic, that of the first excited rotational state J=1J=1J=1 is anisotropic and depends strongly on the light polarization angle. We obtain both polarizabilities precisely by combining trap oscillation frequency measurement and high-resolution rotational spectroscopy driven by microwave. With the optimized light polarization angle and intensity combination, the nonuniformity of the differential AC Stark shift between the two rotational states is minimized and the rotational coherence time is observed to be the longest.