Atom three-level

X. Chen, 1. Lizuain, A. Ruschhaupt, D. Gudry-Odelin, and J. G. Muga, Shortcut to adiabatic passage in two- and three-level atoms. Phys. Rev. Lett, 105(12) 123003—123006(2010). 

D. A. Hutchinson, K. J. Woloschuk, and C. Mavroyannis, Physica 123C, 319 (1984). Third-Order Nonlinear Spectra of a Strong Bichromatic Field Interacting with a Three-Level Atom in a V Configuration. 

The interest in quantum interference stems from the early 1970s when Agarwal [4] showed that the ordinary spontaneous decay of an excited degenerate V-type three-level atom can be modified due to interference between the two atomic transitions. The analysis of quantum interference has since been extended to other configurations of three- and multilevel atoms and many interesting effects have been predicted, which can be used to control optical properties of quantum systems, such as high-contrast resonances [5,6], electro-magnetically induced transparency [7], amplification without population inversion [8], and enhancement of the index of refraction without absorption [9]. 

The discussion, presented in Section IV, has been concentrated on analysis of the effect of quantum interference on spontaneous emission in a V-type three-level atom. With the specific examples we have demonstrated that spontaneous emission can be controlled and even suppressed by quantum interference. In this section, we extend the analysis to the case of coherently driven systems. We will present simple models for quantum interference in which atomic systems are composed of two coupled dipole subsystems. In particular, we consider interference effects in coherently driven V and A-type three-level atoms. Each of the three systems is represented by two dipole moments, p, and p2, interacting through the vacuum field. 

Another area of interest in quantum interference effects, which has been studied extensively, is the response of a V-type three-level atom to a coherent laser field directly coupled to the decaying transitions. This was studied by Cardimona et al. [36], who found that the system can be driven into a trapping state in which quantum interference prevents any fluorescence from the excited levels, regardless of the intensity of the driving laser. Similar predictions have been reported by Zhou and Swain [5], who have shown that ultrasharp spectral lines can be predicted in the fluorescence spectrum when the dipole moments of the atomic transitions are nearly parallel and the fluorescence can be completely quenched when the dipole moments are exactly parallel. 

The narrow resonances produced by quantum interference may also be observed in the absorption spectrum of a three-level atom probed by a weak field of the frequency o> ). Zhou and Swain [10] have calculated the absorption spectrum of a probe field monitoring E-type three-level atoms with degenerate (A = 0) as well as nondegenerate (A / 0) transitions and have demonstrated that quantum... 

Consider the Menon-Agarwal approach to the Autler-Townes spectrum of a V-type three-level atom. The atom is composed of two excited states, 1) and 3), and the ground state 2) coupled by transition dipole moments with matrix elements p12 and p32, but with no dipole coupling between the excited states. The excited states are separated in frequency by A. The spontaneous emission rates from 1) and 3) to the ground state 2) are Tj and T2, respectively. The atom is driven by a strong laser field of the Rabi frequency il, coupled solely to the 1) —> 2) transition. This is a crucial assumption, which would be difficult to realize in practice since quantum interference requires almost parallel dipole moments. However, the difficulty can be overcome in atomic systems with specific selection rules for the transition dipole moments, or by applying fields with specific polarization properties [26]. 

Zhou and Swain [65] have also shown that the idea of the preselected polarization can be applied to engineer a system with antiparallel dipole moments. Zhou [66] has extended the method to a cascade three-level atom coupled to a frequency-tunable cavity mode in a thermal state. 

Kozhekin et al. [38] proposed a method of mapping of quantum states onto an atomic system based on the stimulated Raman absorption of propagating quantum light by a cloud of three-level atoms. Hald et al. [40] have experimentally observed the squeezed spin states of a system of three-level atoms driven by a squeezed held. The observed squeezed spin states have been generated via entanglement exchange with the squeezed held completely absorbed in the process. Fleishhauer et al. [39] have considered a similar system of three-level atoms and have found that quantum states of single-photon helds can be mapped onto collective states of the atomic system. In this case the quantum state of the held is stored in a dark state of the collective states of the system. 

E. Paspalakis, S.-Q. Gong, P. Knight, Spontaneous emission-induced coherent effects in absorption and dispersion of a V-type three-level atom, Opt. Commun. 152 (1998) 293. 

Fig. 2. Possible nonlinear processes for dressed three-level atom ...

Chapter 1. Cavity Linewidth Controls with an Intracavity Three-level Atomic Medium... 

The Chapter is organized as follows. First the theoretical calculations with A -type three-level atoms in the optical ring cavity are described. The EIT-enhanced linear and nonlinear dispersions are calculated, and their effects to the cavity linewidth are discussed in different parametric regions. Second, various experimental observations are presented to demonstrate those interesting effects on cavity linewidth narrowing and broadening, as well as WLC. The last part serves as the summary with some discussions. 

Wang H, Goorskey D, and Xiao M. Enhanced Kerr nonlinearity via atomie eoherenee in a three-level atomic system. Physical Review Letters 2001Aug 13 87(7) 073601(4). 

Rabi frequeney of the eoupling laser and result in two transition paths ( l> +> and 1>—> ->) for the probe laser (Fig. 1(b)). On the resonance frequency of the bare state transition 1> —> 3>, the quantum interferenee between the two transition paths is destructive due to the opposite frequency detuning and leads to the suppression of the probe light absorption, rendering the three-level atomic medium transparent to the probe laser. Since the two transitions are linear and are connected by the same probe laser field, the quantum interference is independent of the probe laser phase and is destructive only. 

H. Wang, D. Goorskey, and M. Xiao. Enhanced Kerr Nonlinearity via Atomic Coherence in a Three-Level Atomic System. Physical Review Letters 2001 Jul 26 87(7) 073601(4). 

Quantum-beat lasers are a particular form of correlated spontaneous emission lasers (CEL s) [43-49]. Quantum-beat is formed by creating coherence between near degenerate atomic states, either excited states or ground states. In particular, a beam of three-level atoms in Vee configuration emit photons into two modes. The atomic upper levels are initially prepared in a coherent superposition or are coupled by a coherent field [13-17]. The fluetuations of the relative phase and the relative amplitude drop to the vacuum levels. In addition to this, as a different form, correlated spontaneous emission can be formed by creating eoherenee between a pair of states between which lasing transitions occm. One such example is a two-photon CEL [13-17] with a beam of three-level atoms in cascade configuration. The top and bottom states are initially prepared in a coherent superposition state. It was predicted that the phase noise is reduced by 50% below the vacuum noise level. 

Figure 1 Three-level atoms with dipole transitions 1,2)- 3) in the Lambda configuratioa Two external coherent fields are coupled to the dipole transitions (half Rabi frequencies Qi 2) and detuned asymmetrically with respect to respective transitions (Ai=-A2=A). Two cavity fields (oi 2) are generated from Rabi sidebands.

Figure 9 Three-level atoms with dipole transitions 1,2>- 3) in the Lambda configuration. The dipole forbidden transition between two metastable states 1> and 2) are coupled to each other via microwave transition (a), or Raman transition (b), or two-photon transition (c) with effective half Rabi frequency Qo Another optical field is resonantly coupled to the dipole transition 2)- 3> with half Rabi frequency Qi. The two cavity fields 012 are amplified from Rabi sidebands on the dipole transition 1)- 3>.

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