Two-photon-resonant excitation of the sodium $3d$ level can lead to the generation of new frequencies either by amplified spontaneous emission at the $3d\ensuremath{\rightarrow}3p$ transition frequency or by a resonantly enhanced four-wave mixing process. Competition between these two processes has been observed. The four-wave mixing process can suppress amplified spontaneous emission by preventing the excitation of the $3d$ level due to an interference between two different pathways connecting the ground ( $3s$ ) and $3d$ states.Two-photon-resonant excitation of the sodium $3d$ level can lead to the generation of new frequencies either by amplified spontaneous emission at the $3d\ensuremath{\rightarrow}3p$ transition frequency or by a resonantly enhanced four-wave mixing process. Competition between these two processes has been observed. The four-wave mixing process can suppress amplified spontaneous emission by preventing the excitation of the $3d$ level due to an interference between two different pathways connecting the ground ($3s$) and $3d$ states.

Physical Review LettersSep 2, 1985108 citations

Observation of the interplay between seeded and self-seeded nondegenerate four-wave mixing in cesium vapor

Yueying Zhang, Jinze Wu, Yanyan He +4 more

Nondegenerate four-wave mixing (NFWM) is a practical and effective technique for generating or amplifying light fields at different wavelengths, and could be used to create color correlation and entanglement. Here we experimentally investigate the NFWM process in diamond atomic system via two-photon excitation with two pumps at 852 nm and 921 nm, demonstrating that a seeded NFWM with a third laser at 895 nm and two self-seeded NFWMs due to amplified spontaneous emission (ASE) occur simultaneously. We compare the two kinds of processes and show that the single- and two-photon detunings hold the key role in distinguishing them. As a result, the enhancement of seeded NFWM is obtained by selecting large one- and two-photon detunings, in which case the ASE induced self-seeded NFWM can be largely suppressed. In contrast, the ASE and its induced NFWM are effectively achieved with one- and two-photon resonant excitations allowing for population inversion for efficient ASE.Nondegenerate four-wave mixing (NFWM) is a practical and effective technique for generating or amplifying light fields at different wavelengths, and could be used to create color correlation and entanglement. Here we experimentally investigate the NFWM process in diamond atomic system via two-photon excitation with two pumps at 852 nm and 921 nm, demonstrating that a seeded NFWM with a third laser at 895 nm and two self-seeded NFWMs due to amplified spontaneous emission (ASE) occur simultaneously. We compare the two kinds of processes and show that the single- and two-photon detunings hold the key role in distinguishing them. As a result, the enhancement of seeded NFWM is obtained by selecting large one- and two-photon detunings, in which case the ASE induced self-seeded NFWM can be largely suppressed. In contrast, the ASE and its induced NFWM are effectively achieved with one- and two-photon resonant excitations allowing for population inversion for efficient ASE.

Optics ExpressMay 20, 202018 citations

Four-wave mixing with matter waves

Li Deng, E. W. Hagley, Jiping Wen +7 more

NatureMar 1, 1999449 citations

Classical Aspects of Spontaneous Emission

ALBERT ROSE

WORLD SCIENTIFIC eBooksApr 1, 19890 citations

Effect of spontaneous emission and recombination on the four-wave—mixing profiles involving autoionizing resonances

G. S. Agarwal, P. Anantha Lakshmi

A general expression for the four-wave---mixing profiles in situations involving autoionizing resonances is derived by taking fully into account the spontaneous-emission characteristics of the autoionizing states. The signals are valid for arbitrary values of Fano asymmetry parameters, field strengths, and spontaneous-emission rates. The dramatic increase in the four-wave---mixing signal for field strengths corresponding to the confluence is demonstrated. The spontaneous emission is shown to affect the line shapes not only in weak fields but also in strong fields. The effects of spontaneous emission are found to be most important for field strengths corresponding to confluence which is similar to the problem of laser-induced autoionization.A general expression for the four-wave---mixing profiles in situations involving autoionizing resonances is derived by taking fully into account the spontaneous-emission characteristics of the autoionizing states. The signals are valid for arbitrary values of Fano asymmetry parameters, field strengths, and spontaneous-emission rates. The dramatic increase in the four-wave---mixing signal for field strengths corresponding to the confluence is demonstrated. The spontaneous emission is shown to affect the line shapes not only in weak fields but also in strong fields. The effects of spontaneous emission are found to be most important for field strengths corresponding to confluence which is similar to the problem of laser-induced autoionization.

Physical Review ADec 1, 19837 citations

Two-photon-resonant excitation of the sodium

3d

level can lead to the generation of new frequencies either by amplified spontaneous emission at the $3d\ensuremath{\rightarrow}3p$ transition frequency or by a resonantly enhanced four-wave mixing process. Competition between these two processes has been observed. The four-wave mixing process can suppress amplified spontaneous emission by preventing the excitation of the

3d

level due to an interference between two different pathways connecting the ground (

3s

) and

3d

states.