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

Journal of the Optical Society of America B

Deflection of atoms by standing-wave radiation

Philip E. Moskowitz, P. L. Gould, David E. Pritchard

Published Nov 1, 1985• 32 citations
Publisher

Abstract

We have observed momentum transfer from a standing-wave light field to an atomic beam. The atomic beam is split symmetrically into two peaks whose separation increases with field strength. The short interaction time ensures that this deflection is due to induced forces; these are described using a semiclassical dressed-atom treatment, which gives good agreement with the data. In addition to the splitting, we have observed diffraction of the atomic beam due to the exchange of even numbers of photons with the field.

DOI
10.1364/josab.2.001784

Related papers

Diffraction of an Atomic Beam by Standing-Wave Radiation

Philip E. Moskowitz, P. L. Gould, Susan R. Atlas +1 more

Preliminary experimental results are reported for the deflection of Na atoms in an atomic beam by a transverse standing-wave laser field whose frequency is tuned between the two ground-state hyperfine components of the ${D}_{2}$ line. In contrast to the two experiments done previously, a splitting of the beam into two symmetric peaks whose separation increases with the electric-field is seen here. In addition, the data show evidence for atomic diffraction: a tendency for scattered atoms to acquire momentum in multiples of $2\ensuremath{\hbar}k$.

Physical Review Letters•Aug 1, 1983•169 citations

Experimental study of light forces on atoms: diffraction and diffusion

P. L. Gould, George A. Ruff, Peter J. Martin +3 more

We have observed both diffractive and diffusive regimes in the transfer of momentum to an atomic beam by a standing-wave radiation field. The momentum transfer was measured by passing a well-collimated beam of sodium atoms through a focused standing-wave laser waist. A narrow velocity distribution beam was obtained by utilizing a supersonic expansion and a two-state system was realized by optically pumping the beam prior to the interaction. The transverse momentum transferred to the atomic beam by the radiation field was measured by scanning a detector downstream from the interaction. The overall momentum resolution of the apparatus is less than the momentum of a single photon. The transition from diffractive to diffusive behavior is associated with an increase in the average number of spontaneous decays occurring during the interaction. In the diffractive regime, spontaneous decay is insignificant and momentum transfer proceeds by pairs of absorption/stimulated emission processes. This produces momentum exchange quantized in even multiples of photon momentum, the so-called Kapitza-Dirac effect; the deflection patterns show oscillatory structure. In the diffusive regime, spontaneous decay is important and causes fluctuations in the radiative forces. In addition, the recoil distribution associated with spontaneous decay results in a washing out of the diffraction peaks associated with stimulated processes, resulting in a smooth deflection pattern.

International Laser Science Conference•Jan 1, 1986•0 citations

Atomic beam deflection in a quantum field

Pierre Meystre, E. Schumacher, Stig Stenholm +1 more

We investigate to which extent the quantum nature of light modifies laser-induced atomic beam deflection in a plane standing wave. Our model considers a single two-level atom interacting with a single quantized standing wave mode of the electromagnetic field. We neglect spontaneous emission into other field modes, an approximation valid for short enough times. We find that there is an essential qualitative difference between the cases of a coherent field and a thermal field. For a coherent field, the atomic momentum distribution after interaction has two symmetric peaks on the wings and resembles the semiclassical result of Arimondo et al. [Phys. Rev. A 24, 898 (1981)]. For a thermal field, this distribution has its maximum at p = 0. It is characterized by a constant contribution at p = 0, some sharp interference features, and near-Gaussian wings. The only feature common to both cases is that in the Raman-Nath regime of scattering, the range on transverse momenta grows linearly with time at a rate proportional to 〈 n 〉 , where 〈 n 〉 is the mean number of photons in the field.

Annual Meeting Optical Society of America•Jan 1, 1989•3 citations

Deflection of atoms by a resonant standing electromagnetic wave

R. J. Cook, Anthony F. Bernhardt

Deflection of an atom due to momentum transfer from a strong resonant standing electromagnetic wave is investigated theoretically in the limit of short atom-field interaction time. The translational and internal motions of the atom are treated quantum mechanically, while the field is treated classically. It is shown that momentum transfer from a standing wave to an atom proceeds at the induced or Rabi rate, rather than the spontaneous rate characteristic of radiation pressure. In a typical case, atomic deflections of order 1\ifmmode^\circ\else\textdegree\fi{} are achieved with ${10}^{6}$ W/${\mathrm{cm}}^{2}$ field intensity in a time less than the natural lifetime of the excited atom.

Physical Review A•Dec 1, 1978•135 citations

Deflection of an Atomic Beam in a Large Period Quantized Standing Light Wave

Xiaoguang Wang, Chang-Pu Sun

By using the Wei-Norman's method, the deflection of an atomic beam with a large period quantized standing light wave is analyzed for the case with two-level atom and single-mode cavity field. It is concluded that after passing through the standing light wave in cavity, the atomic beam is split into infinite beams symmetrically, and each momentum shift for a split component is proportional to the interaction time. It is also shown that the output momentum distribution of atoms is sensitive to the statistical properties of the cavity field.

Chinese Physics Letters•Dec 1, 1994•2 citations

Diffraction of atoms by light: The near-resonant Kapitza-Dirac effect

P. L. Gould, George A. Ruff, David E. Pritchard

We have observed the Kapitza-Dirac effect in the scattering of sodium atoms by a nearly resonant standing-wave laser field. The data clearly show diffraction peaks of the atomic momentum transfer at even multiples of the photon momentum. Theoretical predictions for an off-resonant, adiabatic interaction with a two-state system are in reasonable agreement with the data.

Physical Review Letters•Feb 24, 1986•408 citations
We have observed momentum transfer from a standing-wave light field to an atomic beam. The atomic beam is split symmetrically into two peaks whose separation increases with field strength. The short interaction time ensures that this deflection is due to induced forces; these are described using a semiclassical dressed-atom treatment, which gives good agreement with the data. In addition to the splitting, we have observed diffraction of the atomic beam due to the exchange of even numbers of photons with the field.
Preliminary experimental results are reported for the deflection of Na atoms in an atomic beam by a transverse standing-wave laser field whose frequency is tuned between the two ground-state hyperfine components of the D2{D}_{2}D2​ line. In contrast to the two experiments done previously, a splitting of the beam into two symmetric peaks whose separation increases with the electric-field is seen here. In addition, the data show evidence for atomic diffraction: a tendency for scattered atoms to acquire momentum in multiples of $2\ensuremath{\hbar}k$.
We have observed both diffractive and diffusive regimes in the transfer of momentum to an atomic beam by a standing-wave radiation field. The momentum transfer was measured by passing a well-collimated beam of sodium atoms through a focused standing-wave laser waist. A narrow velocity distribution beam was obtained by utilizing a supersonic expansion and a two-state system was realized by optically pumping the beam prior to the interaction. The transverse momentum transferred to the atomic beam by the radiation field was measured by scanning a detector downstream from the interaction. The overall momentum resolution of the apparatus is less than the momentum of a single photon. The transition from diffractive to diffusive behavior is associated with an increase in the average number of spontaneous decays occurring during the interaction. In the diffractive regime, spontaneous decay is insignificant and momentum transfer proceeds by pairs of absorption/stimulated emission processes. This produces momentum exchange quantized in even multiples of photon momentum, the so-called Kapitza-Dirac effect; the deflection patterns show oscillatory structure. In the diffusive regime, spontaneous decay is important and causes fluctuations in the radiative forces. In addition, the recoil distribution associated with spontaneous decay results in a washing out of the diffraction peaks associated with stimulated processes, resulting in a smooth deflection pattern.
We investigate to which extent the quantum nature of light modifies laser-induced atomic beam deflection in a plane standing wave. Our model considers a single two-level atom interacting with a single quantized standing wave mode of the electromagnetic field. We neglect spontaneous emission into other field modes, an approximation valid for short enough times. We find that there is an essential qualitative difference between the cases of a coherent field and a thermal field. For a coherent field, the atomic momentum distribution after interaction has two symmetric peaks on the wings and resembles the semiclassical result of Arimondo et al. [Phys. Rev. A 24, 898 (1981)]. For a thermal field, this distribution has its maximum at p = 0. It is characterized by a constant contribution at p = 0, some sharp interference features, and near-Gaussian wings. The only feature common to both cases is that in the Raman-Nath regime of scattering, the range on transverse momenta grows linearly with time at a rate proportional to 〈 n 〉 , where 〈 n 〉 is the mean number of photons in the field.
Deflection of an atom due to momentum transfer from a strong resonant standing electromagnetic wave is investigated theoretically in the limit of short atom-field interaction time. The translational and internal motions of the atom are treated quantum mechanically, while the field is treated classically. It is shown that momentum transfer from a standing wave to an atom proceeds at the induced or Rabi rate, rather than the spontaneous rate characteristic of radiation pressure. In a typical case, atomic deflections of order 1\ifmmode^\circ\else\textdegree\fi{} are achieved with 106{10}^{6}106 W/cm2{\mathrm{cm}}^{2}cm2 field intensity in a time less than the natural lifetime of the excited atom.
By using the Wei-Norman's method, the deflection of an atomic beam with a large period quantized standing light wave is analyzed for the case with two-level atom and single-mode cavity field. It is concluded that after passing through the standing light wave in cavity, the atomic beam is split into infinite beams symmetrically, and each momentum shift for a split component is proportional to the interaction time. It is also shown that the output momentum distribution of atoms is sensitive to the statistical properties of the cavity field.