Resonance phenomena in saturation of absorption by laser radiation

Letokhov, V. S.; Chebotaev, V. P.

doi:10.1070/pu1975v017n04abeh004422

Cited by 20 publications

(15 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The random laser was first predicted theoretically by Letokhov in 1968 [1] and was then observed experimentally by Lawandy [2] in dye solution and by Cao [3] in ZnO powder. Since then, the random laser has received considerable interest, and extensive reports have been published because it has introduced a new world of mirrorless lasers and shown that scattering can also be constructive for lasing.…”

Section: Introductionmentioning

confidence: 93%

Inflection point of the spectral shifts of the random lasing in dye solution with TiO₂nanoscatterers

Fan¹,

Zhang²,

Wang³

et al. 2008

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

We report the inflection point of the spectral shift of random lasing, from blue shift to red shift, in Rhodamine 6G dye solution with TiO2 nanoscatterers under picosecond pulses pumping, on increasing the scatterer density for certain dye concentrations. The red shift, resulting from the re-absorption and re-emission of the dye, indicates a longer optical path length of the emitted laser travelling inside the media. The diffusion theory is provided to show the discrepancy in the theory and the experimental results, which show that the light stays in the medium longer than the theory predicts. So this inflection point shows that the system changes from a diffusion system to a weakly localized one. The spectral width shows similar behaviour, for a longer optical path length results in a broader spectral width.

show abstract

Section: Introductionmentioning

confidence: 93%

Inflection point of the spectral shifts of the random lasing in dye solution with TiO₂nanoscatterers

Fan¹,

Zhang²,

Wang³

et al. 2008

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

show abstract

“…Random laser, first theoretically proposed by Letokhov in 1968 and experimentally demonstrated afterward, provides a possible answer to solve the shortcomings of the conventional laser. 15 The random lasing system used multiple scattering inside disordered materials instead of mirrors to form closed loops that trapped light and induced amplified feedback. With this unique feedback mechanism caused by multiple scattering, spiky stimulated peaks based on the feedback mechanism determined by scattering, the mean free path could be found in the spectrum when about the threshold, also known as one of the distinguishing features of random lasers.…”

Section: Introductionmentioning

confidence: 99%

Speckle-Free, Angle-Free, Cavity-Free White Laser with a High Color Rendering Index

Hou,

Tsui,

Chou

et al. 2024

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

The freedom from efficiency droop motivates monochromatic lasers to progress in general lighting applications due to the demand for more efficient and sustainable light sources. Still, a white light based on monochromatic lasers with high lighting quality, such as a high color rendering ability, an angle-independent output, and a speckle-free illumination, has not yet been fabricated nor demonstrated. Random lasers, with the special mechanism caused by multiple scattering, the angle-free emission, and the uncomplicated fabrication processes, inspire us to investigate the feasibility of utilizing them in general lighting. In this work, a white random laser with a high color rendering index (CRI) value, regardless of pumping energy and observing direction, was performed and discussed. We also investigated the stability of white RL as its CIE chromaticity coordinates exhibit negligible differences with increasing pump energy density, retaining its high-CRI measurement. Also, it exhibits angleindependent emission while having a high color rendering ability. After passing through a scattering film, it generated no speckles compared to the conventional laser. We demonstrated the advances in white laser illumination, showing that a white random laser is promising to be applied for high-brightness illumination, biological-friendly lighting, accurate color selections, and medical sensing.

show abstract

“…Random lasers (RLs) are based on the propagation of light in scattering materials with gain [1][2][3][4]. Due to the absence of a well-defined optical cavity, which usually is composed of a couple of mirrors, the RL emission was considered an amplification of the spontaneous emission rather than a true laser in the sense of oscillations [5].…”

Section: Introductionmentioning

confidence: 99%

Gain clamping in random lasers

Santos¹,

Silva²,

Silva³

et al. 2021

Laser Phys. Lett.

View full text Add to dashboard Cite

Random lasers (RLs) rely on obtaining laser emission in disordered systems with gain. The characterization of the RLs are performed by the observations of bandwidth narrowing, increasing in the slope efficiency, time shortening of the upper level of the RL transition, intensity and spectral fluctuations, and even photon statistics transitions when increasing the optical gain. However, the gain clamping, which is a known phenomenon in conventional lasers, i.e. lasers with well-defined cavity, was never investigated in RLs. Here we realize an experimental-theoretical investigation of the gain clamping in RLs, and demonstrate that it can be used as an alternative tool to characterize the transition from spontaneous emission to the RL regime.

show abstract

Resonance phenomena in saturation of absorption by laser radiation

Cited by 20 publications

References 3 publications

Inflection point of the spectral shifts of the random lasing in dye solution with TiO₂nanoscatterers

Inflection point of the spectral shifts of the random lasing in dye solution with TiO₂nanoscatterers

Speckle-Free, Angle-Free, Cavity-Free White Laser with a High Color Rendering Index

Gain clamping in random lasers

Contact Info

Product

Resources

About

Resonance phenomena in saturation of absorption by laser radiation

Cited by 20 publications

References 3 publications

Inflection point of the spectral shifts of the random lasing in dye solution with TiO2nanoscatterers

Inflection point of the spectral shifts of the random lasing in dye solution with TiO2nanoscatterers

Speckle-Free, Angle-Free, Cavity-Free White Laser with a High Color Rendering Index

Gain clamping in random lasers

Contact Info

Product

Resources

About

Inflection point of the spectral shifts of the random lasing in dye solution with TiO₂nanoscatterers

Inflection point of the spectral shifts of the random lasing in dye solution with TiO₂nanoscatterers