Switching from positive to negative dispersion in a three-level V system driven by a single coherent field

Hu, Xiangming; Du, Dan; Cheng, Guangling; Zou, Jin-hua; Li, Xing

doi:10.1088/0953-4075/38/7/005

Cited by 11 publications

(4 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Agarwal et al [38] proposed an N system and demonstrated that the dispersion switching occurred as the intensity of the additional coupling field was increased. The experimental demonstration was realized by Kang et al [39] and they measured a slow group velocity ∼ 3 × 10 −4 c and a negative group velocity of ∼ −4 × 10 −4 c. Hu et al [40] showed that the change from positive to negative dispersion with increasing intensity of the driving field is achievable in the V system, which is the same as in the system. In another paper [41], they presented a theoretical analysis of double switching from normal to anomalous dispersion via trichromatic phase manipulation of electromagnetically induced transparency.…”

Section: Introductionmentioning

confidence: 95%

Control over group velocity in a three-level closed Λ system via spontaneously generated coherence and dynamically induced coherence

Dutta¹,

Dastidar²

2007

J. Phys. B: At. Mol. Opt. Phys.

View full text Add to dashboard Cite

The light propagation of a probe field in a three-level Λ system with incoherent pumping has been studied when both dynamically induced coherence (DIC) and spontaneously generated coherence (SGC) play a significant role. We have investigated the group velocity of probe field and hence the group index of a three-level Λ system with incoherent pumping when both DIC and SGC play a significant role. We have shown that by varying the probe field Rabi frequency one can control the interference between these two coherences which leads to different nonlinear response (amplification without inversion, electromagnetically induced transparency and electromagnetically induced absorption) leading to different (positive and negative) dispersion. Hence control over switching of group velocity from subluminal to superluminal and vice versa can be achieved. We have also shown that when the contributions from both the coherences are comparable, the dependence of group velocity of probe field in a three-level Λ system with incoherent pumping on phase difference between probe and coherent fields is different from that obtained under the weak probe field condition. Going beyond the weak probe field approximation we have derived analytical expressions for group velocity and hence the group index in the steady state limit (keeping all orders of system parameters) to generalize the analysis, and these expressions can be used for any set of system parameters without any restriction. The numerical values obtained by solving the density matrix equations agree well with these exact analytical values at a large time limit. We have proposed a scheme for experimental realization of EIT and hence subluminal light propagation in molecules by invoking spontaneously generated coherence.

show abstract

Section: Introductionmentioning

confidence: 95%

Control over group velocity in a three-level closed Λ system via spontaneously generated coherence and dynamically induced coherence

Dutta¹,

Dastidar²

2007

J. Phys. B: At. Mol. Opt. Phys.

View full text Add to dashboard Cite

show abstract

“…Both the Matrix M and the  can be separated into the terms with different time dependencies as written below [51].…”

Section: Beyond Two-photon Resonance Conditionmentioning

confidence: 99%

Atom–photon entanglement beyond the multi-photon resonance condition

Kordi

Ghanbari

Mahmoudi

2015

Quantum Inf Process

View full text Add to dashboard Cite

The density matrix equations of motion in near-degenerate three-level V-type closedloop atomic system are calculated numerically in Floquet frame. The dynamical behavior of atom-photon entanglement between the dressed atom and its spontaneous emission is studied in semi classical approach beyond the two-photon resonance condition in such a system. The quantum entropy of these two subsystems is investigated by using the von Neumann entropy. It is shown that, the degree of entanglement measure (DEM) can be controlled via the intensity and the detuning of coupling optical field and quantum interference induced by spontaneous emission. Moreover in the absence of quantum interference the steady state behavior of DEM can be achieved even in beyond the two-photon resonance condition. Furthermore in the absence of quantum interference for special parameters of Rabi frequency and detuning of driving laser field disentanglement can be occurred. Also the electromagnetically induced transparency condition can be obtained when the system is disentangled.

show abstract

“…6A. Such a configuration is known in atomic physics as V‐type atom and the dynamics are well understood in terms of a density matrix picture 39, 40. Just as in the case of nuclear magnetic resonance (NMR), we consider the system as being an ensemble of many non‐interacting elements.…”

Section: Perturbed Free Induction Decaymentioning

confidence: 99%

Ultrafast coherent spectroscopy of a single self‐assembled quantum dot

Wolpert

Dicken

Wang

et al. 2012

Physica Status Solidi (b)

View full text Add to dashboard Cite

The controlled interaction of several quantum dots (QDs) mediated by plasmonic or photonic nanostructures promises interesting new functionality in the fields of quantum computing and telecommunication. Ultrafast laser pulses can be used to write and read out the state of the QD. We review ultrafast coherent spectroscopy of single QDs. The focus of this article is on the technique of transient reflection spectroscopy which can be applied to a broad range of samples and devices. It only requires optical access to a single quantum system next to a reflecting surface. We demonstrate the versatility of our approach by presenting several quantum optical studies such as Rabi oscillations, perturbed free induction decay, and quantum beats from an entangled excitonic state in weakly absorbing GaAs QDs. We expect this experimental method to make coherent experiments possible in elaborate devices where quantum emitters are interacting with a complex environment such as plasmonic waveguides or antennas. 1 Introduction In recent years substantial efforts were made to produce matter quantum bits (standing qubits) in various systems [1]. These quantum mechanical two-level systems can be realized by atom-like systems such as single molecules, nitrogen vacancy centers in diamond or semiconductor quantum dots (QDs). Photons are acting as flying quantum bits (qubits) which can be used to transfer quantum information from one stationary qubit to the next and in this way form the connections in a quantum network. Artificial atoms are coupled to cavities or waveguides in order to establish an interface between photons and excitations in matter. In order to produce new photonic devices with novel functionalities one needs not only an efficient quantum system that can be addressed by photons but also controlled coupling to the interconnects.Semiconductor QDs are appealing systems in this context as they are a pure solid-state system which makes them stable, long-lived, and compatible with conventional 2D fabrication techniques. Dephasing times of neutral excitons in QDs can be on the order of several hundreds of

show abstract

Switching from positive to negative dispersion in a three-level V system driven by a single coherent field

Cited by 11 publications

References 35 publications

Control over group velocity in a three-level closed Λ system via spontaneously generated coherence and dynamically induced coherence

Control over group velocity in a three-level closed Λ system via spontaneously generated coherence and dynamically induced coherence

Atom–photon entanglement beyond the multi-photon resonance condition

Ultrafast coherent spectroscopy of a single self‐assembled quantum dot

Contact Info

Product

Resources

About