Electric-field-induced Feshbach resonances in ultracold alkali-metal mixtures
Abstract
We present a detailed analysis of Feshbach resonances in ultracold collisions of Li and Cs atoms in the presence of superimposed electric and magnetic fields. We show that electric fields induce resonances through couplings between the s- and p-wave scattering channels and modify the scattering length to a great extent. Electric-field-induced resonances lead to the anisotropy of ultracold scattering and provide the diagnostics for magnetic p-wave resonances in ultracold gases. We show that the electric field couplings may shift the positions of s-wave magnetic resonances, thereby making the electric field control of ultracold atoms possible even far away from p-wave resonances. Finally, we demonstrate that electric fields may rotate and spin up the collision complex of ultracold atoms at substantial rates.
- Authors:
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1 (Canada)
- Publication Date:
- OSTI Identifier:
- 20982329
- Resource Type:
- Journal Article
- Resource Relation:
- Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevA.75.032709; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 74 ATOMIC AND MOLECULAR PHYSICS; ANISOTROPY; ATOM-ATOM COLLISIONS; ATOMS; CESIUM; COUPLINGS; ELECTRIC FIELDS; GASES; LITHIUM; MAGNETIC FIELDS; MAGNETIC RESONANCE; MIXTURES; P WAVES; S WAVES; SCATTERING; SCATTERING LENGTHS; SPIN; TEMPERATURE RANGE 0000-0013 K
Citation Formats
Li, Z., and Krems, R. V.. Electric-field-induced Feshbach resonances in ultracold alkali-metal mixtures. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVA.75.032709.
Li, Z., & Krems, R. V.. Electric-field-induced Feshbach resonances in ultracold alkali-metal mixtures. United States. doi:10.1103/PHYSREVA.75.032709.
Li, Z., and Krems, R. V.. Thu .
"Electric-field-induced Feshbach resonances in ultracold alkali-metal mixtures". United States.
doi:10.1103/PHYSREVA.75.032709.
@article{osti_20982329,
title = {Electric-field-induced Feshbach resonances in ultracold alkali-metal mixtures},
author = {Li, Z. and Krems, R. V.},
abstractNote = {We present a detailed analysis of Feshbach resonances in ultracold collisions of Li and Cs atoms in the presence of superimposed electric and magnetic fields. We show that electric fields induce resonances through couplings between the s- and p-wave scattering channels and modify the scattering length to a great extent. Electric-field-induced resonances lead to the anisotropy of ultracold scattering and provide the diagnostics for magnetic p-wave resonances in ultracold gases. We show that the electric field couplings may shift the positions of s-wave magnetic resonances, thereby making the electric field control of ultracold atoms possible even far away from p-wave resonances. Finally, we demonstrate that electric fields may rotate and spin up the collision complex of ultracold atoms at substantial rates.},
doi = {10.1103/PHYSREVA.75.032709},
journal = {Physical Review. A},
number = 3,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
-
The effect of random magnetic fields on the dissociation of ultracold molecules with Feshbach resonances is studied analytically. The dissociation spectrum and the evolution of the molecule fraction are obtained for a general form of the magnetic-field ramp and different noise properties relevant to standard experimental conditions. The results uncover the robustness against noise of some characteristics of the dissociation process, in particular, of the dependence of the mean atomic kinetic energy on the system parameters. Implications for the applicability of a method proposed to determine the width of the Feshbach resonances from the measurement of the dissociation spectrum aremore »
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