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Experimental and numerical investigation of single-beam and pump-probe interaction with a resonantly absorbing dense extended medium under strong and weak field-matter coupling is presented. Significant probe beam amplification and conical…

We study the intensity-intensity correlations of the radiation emitted on probe transition in a three level cascade electromagnetically induced transparency (EIT) scheme. By applying an incoherent pump, we also monitor further changes in…

Quantum Physics · Physics 2014-09-04 Shaik Ahmed , Preethi N. Wasnik , Suneel Singh , P. Anantha Lakshmi

We study phase conjugation in a nonlinear composite slab when the counter propagating pump waves are completely absorbed by means of coherent perfect absorption. Under the undepleted pump approximation the coupling constant and the phase…

Optics · Physics 2016-11-29 K. Nireekshan Reddy , Achanta Venu Gopal , S. Dutta Gupta

A theoretical model is developed by exploiting the variational technique to investigate the evolution of an optical beam inside an optically pumped graded-index fiber amplifier. The variational analysis is a semi-analytical method that…

Optics · Physics 2023-10-24 Anuj P. Lara , Samudra Roy , Govind P. Agrawal

The reflection spectrum of a probe light in a -type three-level atomic system coupled by an off-resonant standing-wave is investigated experimentally and theoretically. We show that the maximum value of reflection coefficient occurs when…

Quantum Physics · Physics 2011-02-24 Hai-Tao Zhou , Miao-jun Guo , Da-Wei Wang , Jun-Xiang Zhang , Shi-Yao Zhu

Wang, Kuzmich and Dogariu, in their 20 July, 2000, Nature article, describe an experiment ostensibly measuring superluminal speeds of 310c via a few percent shift in time of an optical pulse undergoing anomalous dispersion in a pumped…

Optics · Physics 2007-05-23 Harry I. Ringermacher , Lawrence R. Mead

We propose an alternative scheme for nonreciprocal light propagation in two coupled cavities system, in which a two-level quantum emitter is coupled to one of the optical microcavities. For the case of parity-time (\textrm{PT}) system…

Quantum Physics · Physics 2016-05-09 A. S. Zheng , G. Zhang , H. Chen , T. Mei , J. Liu

Thanks to the atomic coherence in coupling laser driven atomic system, sub-Doppler absorption has been observed in Doppler-broadened cesium vapor cell via the /Lambda-type three-level scheme. The linewidth of the sub-Doppler absorption peak…

Quantum Physics · Physics 2009-11-10 Junmin Wang , Yanhua Wang , Shubin Yan , Tao Liu , Tiancai Zhang

Enhanced Raman scattering can be obtained by injecting a seeded light field which is correlated with the initially prepared collective atomic excitation. This Raman amplification process can be used to realize atom-light hybrid…

Quantum Physics · Physics 2016-08-24 Zhao-Dan Chen , Chun-Hua Yuan , Hong-Mei Ma , Dong Li , L. Q. Chen , Z. Y. Ou , Weiping Zhang

The interaction of intense, ultra-short laser pulses with nanostructures offers promising avenues for spatiotemporal light control. While enhanced optical transmission through subwavelength apertures has been extensively studied in the…

Optics · Physics 2025-10-31 Xiaohui Gao

Here we report and discuss the avalanche-like up-conversion behavior in absence of the avalanche. We experimentally observed significant changes in the slope of the curve for the intensity dependence of up-conversion luminescence of erbium…

A phenomenological model for spectral broadening of incoherent light in silica fibers via self-phase modulation and dispersion is presented, aiming at providing a qualitative and readily accessible description of incoherent light spectral…

Optics · Physics 2016-11-23 Qinghua Li , Haitao Zhang , Xinglai Shen , He Hao , Mali Gong

We report a simple method to suppress the light shift in optical pumping systems. This method uses only frequency modulation of a radio frequency or microwave source, which is used to excite an atomic resonance, to simultaneously lock the…

Atomic Physics · Physics 2013-02-19 B. H. McGuyer , Y. -Y. Jau , W. Happer

We have observed the propagation of an approximately 35 ns long light pulse with a negative group velocity through a laser-cooled 85Rb atomic medium. The anomalous dispersion results from linear atom-light interaction, and is unrelated to…

We present a microscopic explanation of the controversially discussed transient negative differential transmission observed in degenerate optical pump-probe measurements in graphene. Our approach is based on the density matrix formalism…

Mesoscale and Nanoscale Physics · Physics 2015-06-19 Faris Kadi , Torben Winzer , Ermin Malic , Andreas Knorr

The optical properties of hybrid molecules composed of semiconductor and metal nanoparticles with a weak probe in a strong pump field are investigated theoretically. Excitons in such a hybrid molecule demonstrate novel optical properties…

Mesoscale and Nanoscale Physics · Physics 2008-03-18 Zhien Lu , Ka-di Zhu

Mediated by the interaction with quantum vacuum fields, a laser field propagating in a nonlinear optical medium can generate new light fields via spontaneous parametric process. Such process is inherent independent of the propagation…

We investigate the transient response of a $\Lambda$-type system with one transition decaying to a modified radiation reservoir with an inverse square-root singular density of modes at threshold, under conditions of transparency. We…

Quantum Physics · Physics 2009-10-31 D. G. Angelakis , E. Paspalakis , P. L. Knight

Accurate knowledge of absorption coefficient of a sample is a prerequisite for measuring the third order optical nonlinearity of materials, which can be a serious limitation for unknown samples. We introduce a method, which measures both…

Optics · Physics 2007-05-23 A. Sharan , S. Abbas Hosseini , D. Goswami

We present a theoretical model, using density matrix approach, to study the effect of weak as well as strong probe field on the optical properties of an inhomogeneously broadened multilevel V-system of the $^{87}$Rb D2 line. We consider the…

Atomic Physics · Physics 2015-12-04 Paramjit Kaur , Vineet Bharti , Ajay Wasan