Time-resolved multiphoton effects in the fluorescence spectra of two-level systems at rest and in motion
(2020) In Physical Review A 102(1).- Abstract
We study the time-resolved fluorescence spectrum in two-level systems interacting with an incident coherent field, both in the weak and intermediate coupling regimes. For a single two-level system in the intermediate-coupling case, as time flows, the spectrum develops distinct features that are not captured by a semiclassical treatment of the incident field. Specifically, for a field on resonance with the atomic transition energy, the usual Mollow spectrum is replaced by a four-peak structure, and for a frequency that is half of the atomic transition energy, the time-dependent spectrum develops a second-harmonic peak with a superimposed Mollow triplet. In the long-time limit, our description recovers results previously found in the... (More)
We study the time-resolved fluorescence spectrum in two-level systems interacting with an incident coherent field, both in the weak and intermediate coupling regimes. For a single two-level system in the intermediate-coupling case, as time flows, the spectrum develops distinct features that are not captured by a semiclassical treatment of the incident field. Specifically, for a field on resonance with the atomic transition energy, the usual Mollow spectrum is replaced by a four-peak structure, and for a frequency that is half of the atomic transition energy, the time-dependent spectrum develops a second-harmonic peak with a superimposed Mollow triplet. In the long-time limit, our description recovers results previously found in the literature. After analyzing why a different behavior is observed in the quantum and classical dynamics, the reason for the occurrence of a second-harmonic signal in a two-level system is explained via a symmetry analysis of the total (electron and photon) system and in terms of a three-level system operating in limiting regimes. We find an increased second-harmonic signal in an array of two-level systems, suggesting a superradiance-like enhancement for multiple two-level systems in cavity setups. Finally, initial explorative results are presented for two-level model atoms entering and exiting a cavity, which hint at an interesting interplay between cavity-photon screening and atomic dynamics effects.
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- author
- Viñas Boström, Emil LU ; D'Andrea, Andrea ; Cini, Michele and Verdozzi, Claudio LU
- organization
- publishing date
- 2020
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Physical Review A
- volume
- 102
- issue
- 1
- article number
- 013719
- publisher
- American Physical Society
- external identifiers
-
- scopus:85089264494
- ISSN
- 2469-9926
- DOI
- 10.1103/PhysRevA.102.013719
- language
- English
- LU publication?
- yes
- id
- 1caa9e5e-cdfd-43da-ada4-901510a149b5
- date added to LUP
- 2020-08-18 13:11:42
- date last changed
- 2022-04-19 00:23:36
@article{1caa9e5e-cdfd-43da-ada4-901510a149b5, abstract = {{<p>We study the time-resolved fluorescence spectrum in two-level systems interacting with an incident coherent field, both in the weak and intermediate coupling regimes. For a single two-level system in the intermediate-coupling case, as time flows, the spectrum develops distinct features that are not captured by a semiclassical treatment of the incident field. Specifically, for a field on resonance with the atomic transition energy, the usual Mollow spectrum is replaced by a four-peak structure, and for a frequency that is half of the atomic transition energy, the time-dependent spectrum develops a second-harmonic peak with a superimposed Mollow triplet. In the long-time limit, our description recovers results previously found in the literature. After analyzing why a different behavior is observed in the quantum and classical dynamics, the reason for the occurrence of a second-harmonic signal in a two-level system is explained via a symmetry analysis of the total (electron and photon) system and in terms of a three-level system operating in limiting regimes. We find an increased second-harmonic signal in an array of two-level systems, suggesting a superradiance-like enhancement for multiple two-level systems in cavity setups. Finally, initial explorative results are presented for two-level model atoms entering and exiting a cavity, which hint at an interesting interplay between cavity-photon screening and atomic dynamics effects. </p>}}, author = {{Viñas Boström, Emil and D'Andrea, Andrea and Cini, Michele and Verdozzi, Claudio}}, issn = {{2469-9926}}, language = {{eng}}, number = {{1}}, publisher = {{American Physical Society}}, series = {{Physical Review A}}, title = {{Time-resolved multiphoton effects in the fluorescence spectra of two-level systems at rest and in motion}}, url = {{http://dx.doi.org/10.1103/PhysRevA.102.013719}}, doi = {{10.1103/PhysRevA.102.013719}}, volume = {{102}}, year = {{2020}}, }