We analyze a model where a closed $V$ system is excited by two uncorrelated partially coherent fields. We use a collisionally broadened cw laser, which is a good model for an experimentally realizable partially coherent field, and show that it is possible to generate excited-state coherences even if the two fields are uncorrelated. This transient coherence can be increased if splitting between the excited states is reduced relative to the radiation coherence time ${\ensuremath{\tau}}_{d}$. For small excited-state splitting, one can use this scheme to generate a long-lived coherent response in the system.We analyze a model where a closed $V$ system is excited by two uncorrelated partially coherent fields. We use a collisionally broadened cw laser, which is a good model for an experimentally realizable partially coherent field, and show that it is possible to generate excited-state coherences even if the two fields are uncorrelated. This transient coherence can be increased if splitting between the excited states is reduced relative to the radiation coherence time ${\ensuremath{\tau}}_{d}$. For small excited-state splitting, one can use this scheme to generate a long-lived coherent response in the system.

arXiv:1411.6566Physical Review AApr 30, 20150 citations

Coherent two- and four-particle excitations

A. Arima

Jan 1, 19720 citations

Two-mode excited entangled coherent states and their entanglement properties

Zhou Dong-Lin, Kuang Le-Man

This paper introduces two types of two-mode excited entangled coherent states (TMEECSs) |Ψ±(α, m , n )⟩, studies their entanglement characteristics, and investigates the influence of photon excitations on quantum entanglement. It shows that for the state |Ψ+(α, m , m )⟩ the two-mode photon excitations affect seriously entanglement character while the state |Ψ-(α, m , m )⟩ is always a maximally entangled state, and shows how such states can be produced by using cavity quantum electrodynamics and quantum measurements. It finds that the entanglement amount of the TMEECSs is larger than that of the single-mode excited entangled coherent states with the same photon excitation number.This paper introduces two types of two-mode excited entangled coherent states (TMEECSs) |Ψ±(α, m , n )⟩, studies their entanglement characteristics, and investigates the influence of photon excitations on quantum entanglement. It shows that for the state |Ψ+(α, m , m )⟩ the two-mode photon excitations affect seriously entanglement character while the state |Ψ-(α, m , m )⟩ is always a maximally entangled state, and shows how such states can be produced by using cavity quantum electrodynamics and quantum measurements. It finds that the entanglement amount of the TMEECSs is larger than that of the single-mode excited entangled coherent states with the same photon excitation number.

arXiv:0803.4316Chinese Physics BMar 17, 200914 citations

Method of Coherent States

Lecture notes in physics. M, MonographsJan 1, 19940 citations

Coherent excitation, incoherent excitation, and adiabatic states

D. Grischkowsky

Coherent excitation of an atomic excited state occurs during the propagation of near-resonant light pulses and is responsible for the induced polarization. Simultaneously, incoherent excitation occurs due to the relaxation processes described by the absorption coefficient. Here, the theory for the coherent and incoherent excitation is initially presented in terms of the traditional vector model. While a complete understanding of the two-level system is provided by the vector model, it is shown to be incomplete when the problem of directly monitoring the coherent and incoherent excitation is considered. This is because this latter problem involves more than two levels. For this more complicated multilevel problem, adiabatic states are introduced to gain further understanding. The adiabatic states are the stationary states of the atom in the presence of the near-resonant laser field; they help to explain the intimate connection between the coherent excitation and the two-photon resonance. Experimental measurements of the coherent and incoherent excitation associated with near-resonant pulse propagation in Rb vapor are presented. The double-resonance technique used a relatively strong pulsed dye laser tuned near the $5{S}_{\frac{1}{2}}\ensuremath{\leftrightarrow}5{P}_{\frac{1}{2}}$ transition (7948 \AA{}A) of Rb to produce the coherent and incoherent excitation, and a weak, tunable cw dye laser tuned in the region of the $5{P}_{\frac{1}{2}}\ensuremath{\leftrightarrow}6{D}_{\frac{3}{2}}$ transition (6206 \AA{}A) to monitor this excitation. In agreement with theory, the experimental results demonstrate that coherent excitation is responsible for two-photon absorption, while the incoherent excitation corresponds to one-photon absorption to the $5{P}_{\frac{1}{2}}$ state.Coherent excitation of an atomic excited state occurs during the propagation of near-resonant light pulses and is responsible for the induced polarization. Simultaneously, incoherent excitation occurs due to the relaxation processes described by the absorption coefficient. Here, the theory for the coherent and incoherent excitation is initially presented in terms of the traditional vector model. While a complete understanding of the two-level system is provided by the vector model, it is shown to be incomplete when the problem of directly monitoring the coherent and incoherent excitation is considered. This is because this latter problem involves more than two levels. For this more complicated multilevel problem, adiabatic states are introduced to gain further understanding. The adiabatic states are the stationary states of the atom in the presence of the near-resonant laser field; they help to explain the intimate connection between the coherent excitation and the two-photon resonance. Experimental measurements of the coherent and incoherent excitation associated with near-resonant pulse propagation in Rb vapor are presented. The double-resonance technique used a relatively strong pulsed dye laser tuned near the $5{S}_{\frac{1}{2}}\ensuremath{\leftrightarrow}5{P}_{\frac{1}{2}}$ transition (7948 \AA{}A) of Rb to produce the coherent and incoherent excitation, and a weak, tunable cw dye laser tuned in the region of the $5{P}_{\frac{1}{2}}\ensuremath{\leftrightarrow}6{D}_{\frac{3}{2}}$ transition (6206 \AA{}A) to monitor this excitation. In agreement with theory, the experimental results demonstrate that coherent excitation is responsible for two-photon absorption, while the incoherent excitation corresponds to one-photon absorption to the $5{P}_{\frac{1}{2}}$ state.

Physical Review AAug 1, 197680 citations

Coherent transient excitation

D. Grischkowsky

Optics CommunicationsJul 1, 19762 citations

We analyze a model where a closed

V

system is excited by two uncorrelated partially coherent fields. We use a collisionally broadened cw laser, which is a good model for an experimentally realizable partially coherent field, and show that it is possible to generate excited-state coherences even if the two fields are uncorrelated. This transient coherence can be increased if splitting between the excited states is reduced relative to the radiation coherence time ${\ensuremath{\tau}}_{d}$. For small excited-state splitting, one can use this scheme to generate a long-lived coherent response in the system.

5{P}_{\frac{1}{2}}

state.