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Title: Universality and chaoticity in ultracold K+KRb chemical reactions

Abstract

A fundamental question in the study of chemical reactions is how reactions proceed at a collision energy close to absolute zero. This question is no longer hypothetical: quantum degenerate gases of atoms and molecules can now be created at temperatures lower than a few tens of nanokelvin. Here we consider the benchmark ultracold reaction between, the most-celebrated ultracold molecule, KRb and K. We map out an accurate ab initio ground-state potential energy surface of the K 2Rb complex in full dimensionality and report numerically-exact quantum-mechanical reaction dynamics. The distribution of rotationally resolved rates is shown to be Poissonian. An analysis of the hyperspherical adiabatic potential curves explains this statistical character revealing a chaotic distribution for the short-range collision complex that plays a key role in governing the reaction outcome.

Authors:
 [1];  [2];  [2];  [3];  [4];  [1];  [2]
  1. Univ. of Nevada, Las Vegas, NV (United States)
  2. Temple Univ., Philadelphia, PA (United States)
  3. Temple Univ., Philadelphia, PA (United States); St. Petersburg State Univ. (Russia)
  4. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1414101
Report Number(s):
LA-UR-17-20822
Journal ID: ISSN 2041-1723
Grant/Contract Number:
AC52-06NA25396
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nature Communications
Additional Journal Information:
Journal Volume: 8; Journal ID: ISSN 2041-1723
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Inorganic and Physical Chemistry; Ultracold chemistry, ultracold molecules, quantum reactive scattering

Citation Formats

Croft, J. F. E., Makrides, C., Li, M., Petrov, A., Kendrick, B. K., Balakrishnan, N., and Kotochigova, S.. Universality and chaoticity in ultracold K+KRb chemical reactions. United States: N. p., 2017. Web. doi:10.1038/ncomms15897.
Croft, J. F. E., Makrides, C., Li, M., Petrov, A., Kendrick, B. K., Balakrishnan, N., & Kotochigova, S.. Universality and chaoticity in ultracold K+KRb chemical reactions. United States. doi:10.1038/ncomms15897.
Croft, J. F. E., Makrides, C., Li, M., Petrov, A., Kendrick, B. K., Balakrishnan, N., and Kotochigova, S.. Wed . "Universality and chaoticity in ultracold K+KRb chemical reactions". United States. doi:10.1038/ncomms15897. https://www.osti.gov/servlets/purl/1414101.
@article{osti_1414101,
title = {Universality and chaoticity in ultracold K+KRb chemical reactions},
author = {Croft, J. F. E. and Makrides, C. and Li, M. and Petrov, A. and Kendrick, B. K. and Balakrishnan, N. and Kotochigova, S.},
abstractNote = {A fundamental question in the study of chemical reactions is how reactions proceed at a collision energy close to absolute zero. This question is no longer hypothetical: quantum degenerate gases of atoms and molecules can now be created at temperatures lower than a few tens of nanokelvin. Here we consider the benchmark ultracold reaction between, the most-celebrated ultracold molecule, KRb and K. We map out an accurate ab initio ground-state potential energy surface of the K2Rb complex in full dimensionality and report numerically-exact quantum-mechanical reaction dynamics. The distribution of rotationally resolved rates is shown to be Poissonian. An analysis of the hyperspherical adiabatic potential curves explains this statistical character revealing a chaotic distribution for the short-range collision complex that plays a key role in governing the reaction outcome.},
doi = {10.1038/ncomms15897},
journal = {Nature Communications},
number = ,
volume = 8,
place = {United States},
year = {Wed Jul 19 00:00:00 EDT 2017},
month = {Wed Jul 19 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
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Cited by: 4works
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  • We report on the state-selective detection of near-dissociation ultracold KRb molecules in the ground X {sup 1}{sigma}{sup +} state and the metastable a {sup 3}{sigma}{sup +} state. The molecules are produced by photoassociation of ultracold atoms followed by radiative decay into high vibrational levels of the X and a states. Detection utilizes resonance-enhanced one-color two-photon ionization, followed by time-of-flight mass spectroscopy. Scanning the detection laser frequency over the range 582-625 nm, we observe transitions from the v{sup ''}=86-92 levels of the X state, which are bound by up to 30 cm{sup -1}, and the v{sup ''}=17-23 levels of the amore » state, which are also bound by up to 30 cm{sup -1}. The measured vibrational spacings are in excellent agreement with those previously measured and those calculated from the relevant potential curves. Relative vibrational populations are also consistent with Franck-Condon factors for decay from the photoassociated levels.« less
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