Physical Review A

Dispersion interactions between excited atoms

Gyeong-il Kweon, N. M. Lawandy

Published May 1, 1993• 14 citations

Abstract

We present results on the complete dispersion interaction between two neutral multilevel atoms in the same excited state. The calculations indicate that the dispersion interaction can produce a repulsive barrier of the order of \ensuremath{\simeq}7 \ensuremath{\mu}eV for intermediate separations and that long-range oscillations exist in the Casimir-Polder regime. The results may be of importance in laser-cooled atomic diffusion phenomena where translational energies well below this barrier height are achievable.

DOI: 10.1103/physreva.47.4513

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Physical Review A

Dispersion interactions between excited atoms

Gyeong-il Kweon, N. M. Lawandy

Published May 1, 1993• 14 citations

Publisher

Abstract

DOI: 10.1103/physreva.47.4513

Related papers

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{K}_{7}, {K}_{9},

and

{K}_{11}

long-range coefficients. We have established the range of validity of the Casimir-Polder potential by analyzing the first-order correction to the energy given by the matrix element of the contact interaction term between the atomic charge distributions. Numerical values for the Casimir-Polder long-range interaction potentials for both homonuclear and heteronuclear alkali-metal dimers are presented. Comparisons with previous analytical and numerical results are included.

{K}_{7}, {K}_{9},

and

{K}_{11}

8{S}_{1/2}

of a rubidium atom achieves a positive peak value of about $17\phantom{\rule{0.16em}{0ex}}\ensuremath{\mu}\mathrm{K}$ at a distance of about 150 nm from the fiber surface and becomes strongly repulsive in the region of distances from 150 to 400 nm. We also calculate the nanofiber-induced shifts of the transition frequencies of the atomic rubidium

{D}_{2}

and

{D}_{1}

lines. We find that the shifts are negative in the region of short distances, become positive, and oscillate around the zero value with a decaying amplitude in the region of large distances.