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

Physics Bulletin

Cooled by laser

Published Dec 1, 1981• 0 citations
Publisher

Abstract

If an atom moves towards a source of radiation, the frequency of which is f, it 'sees' a frequency f + Δf and if the latter is one of its natural resonances, it will absorb the photon (energy hf ). Later the atom will return from the excited state, emitting a photon of energy h(f + Δf) and so overall it will have lost hΔf .
DOI
10.1088/0031-9112/32/12/021

Related papers

Entropy Inside The Atoms

Ahmed Elsheekh

All experimental data in atomic physics proved that, emission and absorption processes are completely reverses to each other. Emitted photon is as same as absorbed; excited atom returns to its ground state without any residual tells us there is an action has been done. While studying and interpreting the process of absorption spectra, there is a question that remains unanswered till now, which is; when the electron returns to the ground state, it re-emits the same absorbed photon, but where did this photon go? If it was re-emitted, then the observed absorbed spectrum should appear pale, not completely dark line which mean it has been disappeared. In order to be able to say that the electron lost its energy while returning to its ground state without re-emitting the same absorbed photon or by emitting more than one photon, we must introduce theoretically new energy levels to be attributable to the answer to the question. In this article, we present a mathematical proposal that leads to the inference of new quantized energy levels, where an electron can move among them thermally or spectroscopically. All elements' ionization energy has been proved by using this new mathematical proposal led to results, which are in agreement with National Institute of Standards and Technology (NIST) data. Not only entropy inside the atom has been achieved but also, the disappeared absorbed photon has been explained. At last, our mathematical proposal connected between modern physics and classical physics.

International Journal of Theoretical and Applied Research•Dec 1, 2022•0 citations

Resonance fluorescence of a laser-cooled atom in a non-harmonic potential

Ralf Betzholz, Marc Bienert

arXiv:1605.05951•The European Physical Journal D•Oct 1, 2016•1 citation

Unruh and Cherenkov Radiation from a Negative Frequency Perspective

Anatoly A. Svidzinsky, Arash Azizi, J. Ben-Benjamin +2 more

A ground-state atom uniformly accelerated through the Minkowski vacuum can become excited by emitting an Unruh-Minkowski photon. We show that from the perspective of an accelerated atom, the sign of the frequency of the Unruh-Minkowski photons can be positive or negative depending on the acceleration direction. The accelerated atom becomes excited by emitting an Unruh-Minkowski photon which has negative frequency in the atom's frame, and decays by emitting a positive-frequency photon. This leads to interesting effects. For example, the photon emitted by accelerated ground-state atom cannot be absorbed by another ground-state atom accelerating in the same direction, but it can be absorbed by an excited atom or a ground-state atom accelerated in the opposite direction. We also show that similar effects take place for Cherenkov radiation. Namely, a Cherenkov photon emitted by an atom cannot be absorbed by another ground-state atom moving with the same velocity, but can be absorbed by an excited atom or a ground-state atom moving in the opposite direction.

Physical Review Letters•Feb 12, 2021•25 citations

The slowing down of atoms and the redistribution of atom velocities by the pressure of resonant laser radiation

V. I. Balykin, Vladimir G. Minogin

IzSSR•Jun 1, 1981•0 citations

ATOMIC RADIATION IN THE LASER CONDITIONS, QUANTUM-MECHANICAL STATE OF LASER RADIATION AND THE APPEARANCE OF COHERENCE

Series in optics and photonics•Jan 1, 1994•0 citations

Interference spectra in four-level atomic systems

Constantine Mavroyannis

We have calculated the interference spectra of a single electron in the excited state of a four-level atom interacting with three laser fields, where two of them are on two-photon resonance with the three levels forming a `Λ' scheme while the third laser operates between the second ground and the second excited states of the atom. It is shown that in the low-intensity limit of all three laser fields, the third laser field destroys the destructive interference that occurs between the spontaneous radiative decay and the process arising from the combined field of all the three laser fields. The result is that the overall intensity of the peak at the centre of the line depends on the strength of the third laser field and it takes negative values indicating that light amplification without population inversion (LAWI) is likely to occur at the one-photon frequency. The antisymmetric two-photon state of the two lower levels as well as the two-photon process, where one laser photon is absorbed and another laser photon is emitted simultaneously by the second excited state of the atom, is found to exhibit LAWI at the one-photon frequency. The derived results are graphically presented and discussed.

Journal of Optics B Quantum and Semiclassical Optics•Nov 15, 2000•4 citations
All experimental data in atomic physics proved that, emission and absorption processes are completely reverses to each other. Emitted photon is as same as absorbed; excited atom returns to its ground state without any residual tells us there is an action has been done. While studying and interpreting the process of absorption spectra, there is a question that remains unanswered till now, which is; when the electron returns to the ground state, it re-emits the same absorbed photon, but where did this photon go? If it was re-emitted, then the observed absorbed spectrum should appear pale, not completely dark line which mean it has been disappeared. In order to be able to say that the electron lost its energy while returning to its ground state without re-emitting the same absorbed photon or by emitting more than one photon, we must introduce theoretically new energy levels to be attributable to the answer to the question. In this article, we present a mathematical proposal that leads to the inference of new quantized energy levels, where an electron can move among them thermally or spectroscopically. All elements' ionization energy has been proved by using this new mathematical proposal led to results, which are in agreement with National Institute of Standards and Technology (NIST) data. Not only entropy inside the atom has been achieved but also, the disappeared absorbed photon has been explained. At last, our mathematical proposal connected between modern physics and classical physics.
A ground-state atom uniformly accelerated through the Minkowski vacuum can become excited by emitting an Unruh-Minkowski photon. We show that from the perspective of an accelerated atom, the sign of the frequency of the Unruh-Minkowski photons can be positive or negative depending on the acceleration direction. The accelerated atom becomes excited by emitting an Unruh-Minkowski photon which has negative frequency in the atom's frame, and decays by emitting a positive-frequency photon. This leads to interesting effects. For example, the photon emitted by accelerated ground-state atom cannot be absorbed by another ground-state atom accelerating in the same direction, but it can be absorbed by an excited atom or a ground-state atom accelerated in the opposite direction. We also show that similar effects take place for Cherenkov radiation. Namely, a Cherenkov photon emitted by an atom cannot be absorbed by another ground-state atom moving with the same velocity, but can be absorbed by an excited atom or a ground-state atom moving in the opposite direction.
We have calculated the interference spectra of a single electron in the excited state of a four-level atom interacting with three laser fields, where two of them are on two-photon resonance with the three levels forming a `Λ' scheme while the third laser operates between the second ground and the second excited states of the atom. It is shown that in the low-intensity limit of all three laser fields, the third laser field destroys the destructive interference that occurs between the spontaneous radiative decay and the process arising from the combined field of all the three laser fields. The result is that the overall intensity of the peak at the centre of the line depends on the strength of the third laser field and it takes negative values indicating that light amplification without population inversion (LAWI) is likely to occur at the one-photon frequency. The antisymmetric two-photon state of the two lower levels as well as the two-photon process, where one laser photon is absorbed and another laser photon is emitted simultaneously by the second excited state of the atom, is found to exhibit LAWI at the one-photon frequency. The derived results are graphically presented and discussed.