Spontaneous improvement of spatial coherence and frequency locking in high-pump-power multimode lasers

Papoff, F.; D’Alessandro, Giampaolo

doi:10.1103/physreva.70.063805

Cited by 3 publications

(6 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In (8) we have used the fact that g < 0 in all the physically relevant regimes. No transition is expected for g > 0, as detailed below.…”

Section: Localized Versus Delocalized Modes In the Self-mode-locking ...mentioning

confidence: 99%

“…Unfortunately, at variance with fully-connected (or "mean field") models as (8), analytical treatment of short-range Hamiltonians as ( 10) is almost always impossible and the analysis can only be numerically performed. However, it is well established within the statistical physics community that mean-field models obtained from first-neighborhood systems conserve most of the thermodynamics properties, and more specifically the existence of a thermodynamic transition, at least above the so called "lower critical dimension" d l (for example, for the Ising model is d l = 1, for the XY model is d l = 2).…”

Section: Localized Versus Delocalized Modes In the Self-mode-locking ...mentioning

confidence: 99%

“…The thermodynamic approach to multi-mode interactions in various physical frameworks is well established [7]. For example, it was recently applied to transverse-mode interaction in resonators [8,9], as well as to standard-laser mode-locking transition [10][11][12]. This transition can be described in terms of an effective temperature T , which encompasses the level of noise due to spontaneous emission and the amount of energy stored into each mode.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Mode-locking transitions in nanostructured weakly disordered lasers

et al. 2007

View full text Add to dashboard Cite

We report on a statistical approach to mode-locking transitions of nano-structured laser cavities characterized by an enhanced density of states. We show that the equations for the interacting modes can be mapped onto a statistical model exhibiting a first order thermodynamic transition, with the average mode-energy playing the role of inverse temperature. The transition corresponds to a phase-locking of modes. Extended modes lead to a mean-field like model, while in presence of localized modes, as due to a small disorder, the model has short range interactions. We show that simple scaling arguments lead to observable differences between transitions involving extended modes and those involving localized modes. We also show that the dynamics of the light modes can be exactly solved, predicting a jump in the relaxation time of the coherence functions at the transition. Finally, we link the thermodynamic transition to a topological singularity of the phase space, as previously reported for similar models.

show abstract

“…In (8) we have used the fact that g < 0 in all the physically relevant regimes. No transition is expected for g > 0, as detailed below.…”

Section: Localized Versus Delocalized Modes In the Self-mode-locking ...mentioning

confidence: 99%

Section: Localized Versus Delocalized Modes In the Self-mode-locking ...mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Mode-locking transitions in nanostructured weakly disordered lasers

et al. 2007

View full text Add to dashboard Cite

show abstract

“…Complex processes in laser physics, including nonlinear optics, are well known and studied (see e.g. [30,31]), up to recent investigations in multi-mode systems [32,33,34] and successful reformulations of standard laser thermodynamics [35,36,37,38,39]. The extension of these approaches to RL immediately leads to the application of the statistical theory of disordered systems, of which spin glass theory is a paradigm [40], and which is the subject of the present manuscript.…”

Section: Introductionmentioning

confidence: 99%

Glassy behavior of light in random lasers

et al. 2006

View full text Add to dashboard Cite

A theoretical analysis [Angelani et al., Phys. Rev. Lett. 96, 065702 (2006)] predicts glassy behavior of light in a nonlinear random medium. This implies slow dynamics related to the presence of many metastable states. We consider very general equations (that also apply to other systems, like Bose-Condensed gases) describing light in a disordered non-linear medium and through some approximations we relate them to a mean-field spin-glass-like model. The model is solved by the replica method, and replica-symmetry breaking phase transition is predicted. The transition describes a mode-locking process in which the phases of the modes are locked to random (history and sample-dependent) values. An extended discussion of possible experimental implications of our analysis is reported.

show abstract

“…For example, the KL transform has been recently used to identify and extract spatial features from a complex spatiotemporal evolution in combustion experiment [7,8,9]. A related methodthe so-called biorthogonal decomposition-has also been applied to characterize spatiotemporal chaos and identified structures [10,11] as well as identify changes in the dynamical complexity, and the spatial coherence of a multimode laser [12]. We thus envision that our optimized KL filter may find applications in these and related problems of coherent structures in complex spatiotemporal dynamics.…”

Section: Introductionmentioning

confidence: 99%

Optimized suppression of coherent noise from seismic data using the Karhunen-Loève transform

Montagne

Vasconcelos²

2006

Phys. Rev. E

View full text Add to dashboard Cite

Signals obtained in land seismic surveys are usually contaminated with coherent noise, among which the ground roll (Rayleigh surface waves) is of major concern for it can severely degrade the quality of the information obtained from the seismic record. Properly suppressing the ground roll from seismic data is not only of great practical importance but also remains a scientific challenge. Here we propose an optimized filter based on the Karhunen-Loéve transform for processing seismic data contaminated with ground roll. In our method, the contaminated region of the seismic record, to be processed by the filter, is selected in such way so as to correspond to the maximum of a properly defined coherence index. The main advantages of the method are that the ground roll is suppressed with negligible distortion of the remanent reflection signals and that the filtering can be performed on the computer in a largely unsupervised manner. The method has been devised to filter seismic data, however it could also be relevant for other applications where localized coherent structures, embedded in a complex spatiotemporal dynamics, need to be identified in a more refined way.

show abstract

Spontaneous improvement of spatial coherence and frequency locking in high-pump-power multimode lasers

Cited by 3 publications

References 13 publications

Mode-locking transitions in nanostructured weakly disordered lasers

Mode-locking transitions in nanostructured weakly disordered lasers

Glassy behavior of light in random lasers

Optimized suppression of coherent noise from seismic data using the Karhunen-Loève transform

Contact Info

Product

Resources

About