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

IzSSR

Determination of transverse relaxation time T2 from the shape of a steady-state superluminescence pulse in a molecular medium

Tamara M. Il'inova, Maria V. Bogdanova

Published Aug 1, 1979• 0 citations
OpenAlex

Related papers

Theory of superluminescence in a dispersive medium with molecular relaxation

Maria V. Bogdanova, Tamara M. Il'inova, R. V. Khokhlov

•Feb 1, 1975•0 citations

Contribution to the theory of superluminescence in a dispersive medium with molecular relaxation

Maria V. Bogdanova, Tamara M. Il'inova, R. V. Khokhlov

Zhurnal Eksperimentalnoi i Teoreticheskoi Fiziki•Feb 1, 1975•1 citation

Exact solution of a π-pulse problem

John A. Armstrong, E. Courtens

The exact solution describing steady-state resonant pulse propagation in a two-level inverted medium is given. This steady-state pulse is often referred to as a 180° or π-pulse. No approximation of a slowly varying envelope is made, and hence the solution satisfies the second-order wave equation as well as the equations of motion of the density matrix of the system. As a result the theory is able to describe very short pulses, whose width can be of the order of the period of the optical carrier. The model for the system includes a nonresonant loss and a finite value of the transverse relaxation time T2, but neglects dispersion in the host medium. The steady-state pulse is found to be frequency modulated and asymmetric in shape.

IEEE Journal of Quantum Electronics•Jun 1, 1968•65 citations

Transient Effects, Transverse Mode Coupling, And Diffraction In Swept-Gain Superradiance In The Nonlinear Regime: Evolution From The Superradiant State

Charles M. Bowden, Farrès P. Mattar

Results of numerical calculations are presented and analyzed for pulse generation and propagation in one-and two-spacial dimensions in a medium consisting of a collection of two-level atoms which are resonantly swept-excited by an impulse excitation traveling at the speed of light in the medium. The conditions imposed for the calculation in one-spacial dimension are that T1 = T2, where T1 and T2 are the single atom relaxation and dephasing times, respectively, and that the gain, g, to loss, κ , ratio g/κ >> 1 , which determines the non-linear regime for pulse evolution. In addition, we impose that T2 >> τc, where τc is the characteristic superradiance cooperation time, so that the pulse evolves from conditions appropriate for superradiant pulse generation for sufficiently small values for the propagation distance z . We report and analyze calculational results for the transient regime of pulse buildup through the asymptotic regime of large propagation distance z where the pulse generated exhibits steady-state behavior with regard to pulse area, energy and intensity profile. Additional results of computations are presented which incorporate transverse effects and diffraction using a Gaussian radial gain profile for the initial condition and under imposed conditions comparable with those of the corresponding one-spacial dimension calculations. The results of the two sets of calculations are compared and discussed. We demonstrate and give predictive requirements for swept-gain pulse evolution from the superradiant state.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Jun 16, 1983•1 citation

Two-photon echo method to determine the transverse relaxation time of excitonic molecules

T. Takagahara

Solid State Communications•Apr 1, 1981•3 citations

Storage of optical pulse shapes in spectrally ordered populations

William Randall Babbitt, Yu Bai, T. W. Mossberq

Early in the study of nuclear magnetic resonance, it was recognized that coherent transient signals could possess shapes highly correlated with the radio frequency pulses used to generate them.1 Similar results were observed in the case of optical coherent transients.2 The information necessary to recreate the excitation pulse shapes has traditionally been seen to reside in the polarization of the sample or in the population difference between two energy states. Information so stored is constrained to relax at rates determined by the transverse T2 or the longitudinal T1, relaxation times of the excited nuclear or optical transition. Owing to the shortness of T1 and T2, coherent transient pulse shape storage has been viewed previously as having limited utility.

Conference on Lasers and Electro-Optics•Jan 1, 1985•0 citations
The exact solution describing steady-state resonant pulse propagation in a two-level inverted medium is given. This steady-state pulse is often referred to as a 180° or π-pulse. No approximation of a slowly varying envelope is made, and hence the solution satisfies the second-order wave equation as well as the equations of motion of the density matrix of the system. As a result the theory is able to describe very short pulses, whose width can be of the order of the period of the optical carrier. The model for the system includes a nonresonant loss and a finite value of the transverse relaxation time T2, but neglects dispersion in the host medium. The steady-state pulse is found to be frequency modulated and asymmetric in shape.
Results of numerical calculations are presented and analyzed for pulse generation and propagation in one-and two-spacial dimensions in a medium consisting of a collection of two-level atoms which are resonantly swept-excited by an impulse excitation traveling at the speed of light in the medium. The conditions imposed for the calculation in one-spacial dimension are that T1 = T2, where T1 and T2 are the single atom relaxation and dephasing times, respectively, and that the gain, g, to loss, κ , ratio g/κ >> 1 , which determines the non-linear regime for pulse evolution. In addition, we impose that T2 >> τc, where τc is the characteristic superradiance cooperation time, so that the pulse evolves from conditions appropriate for superradiant pulse generation for sufficiently small values for the propagation distance z . We report and analyze calculational results for the transient regime of pulse buildup through the asymptotic regime of large propagation distance z where the pulse generated exhibits steady-state behavior with regard to pulse area, energy and intensity profile. Additional results of computations are presented which incorporate transverse effects and diffraction using a Gaussian radial gain profile for the initial condition and under imposed conditions comparable with those of the corresponding one-spacial dimension calculations. The results of the two sets of calculations are compared and discussed. We demonstrate and give predictive requirements for swept-gain pulse evolution from the superradiant state.
Early in the study of nuclear magnetic resonance, it was recognized that coherent transient signals could possess shapes highly correlated with the radio frequency pulses used to generate them.1 Similar results were observed in the case of optical coherent transients.2 The information necessary to recreate the excitation pulse shapes has traditionally been seen to reside in the polarization of the sample or in the population difference between two energy states. Information so stored is constrained to relax at rates determined by the transverse T2 or the longitudinal T1, relaxation times of the excited nuclear or optical transition. Owing to the shortness of T1 and T2, coherent transient pulse shape storage has been viewed previously as having limited utility.