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

Communications in Theoretical Physics

Impact of Interacting Quantum Coherence via Decays and Incoherent Pumping on Transient and Steady-State Behaviors of Absorption

Yanfeng Bai, Taigang Liu, Xiaoqiang Yu, Wen‐Xing Yang

Published Apr 1, 2012• 0 citations
Publisher

Abstract

The effects from quantum coherence via decays and incoherent pumping on the lasing without inversion (LWI) are investigated in a four-level system. By analyzing the transient and steady-state behaviors of the absorption, we find that the gain occurs when both spontaneously generated coherence (SGC) and coherence induced by incoherent pumping (IPC) are considered. We attribute the occurrence of the gain to the interaction of quantum coherence via decays and incoherent pumping.

DOI
10.1088/0253-6102/57/4/23

Related papers

Spontaneously Generated Coherence in an Open Four-level Atomic System

Fan Xi-jun

We put forward a model of an open quasi Λ-type four-level atomic system,and then investigate the effect of spontaneously generated coherence(SGC) on the gain of lasing without inversion from different respects by using the numerical calculation results of the system in the steady state.The study results show that,the switching from absorption to lasing without inversion(LWI) and the enhancement of the LWI gain can be realized by adjusting the strength of SGC;the variety of the two factors p1 to p2 which represent the SGC effect will produce remarkable different influence on the LWI gain.We also find that,the LWI gain is much larger in open system than that in the corresponding closed system;moreover,when the incoherent pump field is absent,the LWI gain can be obtained in the open system but cant in the closed system.

Journal of Optoelectronics·laser•Jan 1, 2007•0 citations

Effect of spontaneously generated coherence on transient evolution of LWI gain in an open Ladder type system

Yanling Yang, Lei Wang, Liu Zhong-Bo +3 more

The effect of spontaneously generated coherence （SGC） on transient evolution of gain of lasing without inversion （LWI） and modulation roles of the injection rate ratio and exit rate on SGC-dependent gain in an open Ladder type three level system are studied by using the numerical solution of the density matrix motion equation of the system. It was shown that: variation of SGC strength will make the transient and final stationary gains having a considerable changing; when incoherent pumping presents, LWI gain increases with the ratio of injection rates and exit rate decreasing, however, when incoherent pumping is absent, the case is just the opposite; by choosing suitable values of SGC strength, the injection rate ratio and exit rate, we can obtain the largest transient and final stationary gain.

Acta Physica Sinica•Jan 1, 2009•7 citations

Effects of spontaneously generated coherence on lasing without inversion in a ladder-type three-level atomic system

Cen Jing-sheng

An investigation into lasing without inversion in a Ladder-type three-level atomic system was conducted.With the exhibiting condition of lasing without inversion,the effects of the incoherent pumping and spontaneously generated coherence(SGC) have been studied in detail.The investigation shows that SGC can decrease the phenomena of lasing without inversion(LWI).However,the incoherent pumping can strengthen it.

Journal of Foshan University•Jan 1, 2010•0 citations

Effects of spontaneously generated coherence on the conditions for exhibiting lasing without inversion in a V system

Yanfeng Bai, Hong Mei Guo, Hui Sun +3 more

In this paper, we investigate the effects of spontaneously generated coherence (SGC) on the conditions for exhibiting lasing without inversion (LWI) in the presence of a weak probe and a strong-coupling field. We find that owing to the effect of SGC, LWI can be realized without the incoherent pumping or the decay between two upper levels. However, in the region where LWI can be exhibited, the effect of SGC term on the exhibition of LWI is not always positive, sometimes it can even cumber the realization of LWI for some values of SGC. These values are given in this paper. In addition, we also analyze the essence of the generation of the probe field.

Physical Review A•Apr 19, 2004•57 citations

Effect of Incoherent Pumping on Phase??qdependent Absorption Property of Atomic Systems

Aiyun Li, Feng‐Shou Liu

We find that in the open and closed ladder systems with vacuum induced coherence, the relative phase between the probe and driving fields has an important manipulation role on the absorption property, while the incoherent pumping has a considerable effect on the phase-dependent absorption property.In the both systems, by adjusting the incoherent pumping the switching from absorption to gain and from lasing with inversion to lasing without inversion (LWI) can be realized and the largest LWI gain can be gotten.However, when the incoherent pumping is absent, for any value of the relative phase, LWI still can't be obtained in the closed system but can in the open system; moreover, in the open system, for suitable values of the relative phase, LWI gain gotten when the incoherent pumping is absent is obviously larger than that obtained when the incoherent pumping presents.

International Conference on Social Network, Communication and Education (SNCE)•Jan 1, 2018•0 citations

Phase control of light amplification in steady and transient processes in an inverted-Y atomic system with spontaneously generated coherence

Si-Cong Tian, Cunzhu Tong, Ren-Gang Wan +7 more

We investigate the effects of spontaneously generated coherence (SGC) on both the steady and transient gain properties in a four-level inverted-Y-type atomic system in the presence of a weak probe, two strong coherent fields, and an incoherent pump. For the steady process, we find that the inversionless gain mainly origins from SGC. In particular, we can modulate the inversionless gain by changing the relative phase between the two fields. Moreover, the amplitude of the gain peak can be enhanced and the additional gain peak can appear by changing the detuning of the coupling field. As for the transient process, the transient gain properties can also be dramatically affected by the SGC. Compared to the case without SGC, the transient gain can be greatly enhanced with completely eliminated transient absorption by choosing the proper relative phase between the two fields. And the inverted-Y-type system with SGC can be simulated in both atomic and semiconductor quantum well systems avoiding the conditions of SGC.

Chinese Physics B•Apr 1, 2014•5 citations
The effects from quantum coherence via decays and incoherent pumping on the lasing without inversion (LWI) are investigated in a four-level system. By analyzing the transient and steady-state behaviors of the absorption, we find that the gain occurs when both spontaneously generated coherence (SGC) and coherence induced by incoherent pumping (IPC) are considered. We attribute the occurrence of the gain to the interaction of quantum coherence via decays and incoherent pumping.
We put forward a model of an open quasi Λ-type four-level atomic system,and then investigate the effect of spontaneously generated coherence(SGC) on the gain of lasing without inversion from different respects by using the numerical calculation results of the system in the steady state.The study results show that,the switching from absorption to lasing without inversion(LWI) and the enhancement of the LWI gain can be realized by adjusting the strength of SGC;the variety of the two factors p1 to p2 which represent the SGC effect will produce remarkable different influence on the LWI gain.We also find that,the LWI gain is much larger in open system than that in the corresponding closed system;moreover,when the incoherent pump field is absent,the LWI gain can be obtained in the open system but cant in the closed system.
The effect of spontaneously generated coherence （SGC） on transient evolution of gain of lasing without inversion （LWI） and modulation roles of the injection rate ratio and exit rate on SGC-dependent gain in an open Ladder type three level system are studied by using the numerical solution of the density matrix motion equation of the system. It was shown that: variation of SGC strength will make the transient and final stationary gains having a considerable changing; when incoherent pumping presents, LWI gain increases with the ratio of injection rates and exit rate decreasing, however, when incoherent pumping is absent, the case is just the opposite; by choosing suitable values of SGC strength, the injection rate ratio and exit rate, we can obtain the largest transient and final stationary gain.
In this paper, we investigate the effects of spontaneously generated coherence (SGC) on the conditions for exhibiting lasing without inversion (LWI) in the presence of a weak probe and a strong-coupling field. We find that owing to the effect of SGC, LWI can be realized without the incoherent pumping or the decay between two upper levels. However, in the region where LWI can be exhibited, the effect of SGC term on the exhibition of LWI is not always positive, sometimes it can even cumber the realization of LWI for some values of SGC. These values are given in this paper. In addition, we also analyze the essence of the generation of the probe field.
We find that in the open and closed ladder systems with vacuum induced coherence, the relative phase between the probe and driving fields has an important manipulation role on the absorption property, while the incoherent pumping has a considerable effect on the phase-dependent absorption property.In the both systems, by adjusting the incoherent pumping the switching from absorption to gain and from lasing with inversion to lasing without inversion (LWI) can be realized and the largest LWI gain can be gotten.However, when the incoherent pumping is absent, for any value of the relative phase, LWI still can't be obtained in the closed system but can in the open system; moreover, in the open system, for suitable values of the relative phase, LWI gain gotten when the incoherent pumping is absent is obviously larger than that obtained when the incoherent pumping presents.
We investigate the effects of spontaneously generated coherence (SGC) on both the steady and transient gain properties in a four-level inverted-Y-type atomic system in the presence of a weak probe, two strong coherent fields, and an incoherent pump. For the steady process, we find that the inversionless gain mainly origins from SGC. In particular, we can modulate the inversionless gain by changing the relative phase between the two fields. Moreover, the amplitude of the gain peak can be enhanced and the additional gain peak can appear by changing the detuning of the coupling field. As for the transient process, the transient gain properties can also be dramatically affected by the SGC. Compared to the case without SGC, the transient gain can be greatly enhanced with completely eliminated transient absorption by choosing the proper relative phase between the two fields. And the inverted-Y-type system with SGC can be simulated in both atomic and semiconductor quantum well systems avoiding the conditions of SGC.