EFFECT OF PHASE FLUCTUATIONS OF LASER ON OPTICAL FORCES IN A TWO-LEVEL ATOM

An effect of phase fluctuations of a driving laser field on dissipative and dipolar forces of two-level atom is considered. The phase fluctuations are treated by a phase diffusion model where phase fluctuations follow Wiener–Levy process. An exact master equation for the relevant density operator is obtained and solved in the steady state. Optical forces are calculated. The effect of phase fluctuations on angular momentum imparted by a Laguerre–Gaussian beam and an ideal Bessel beam to the atom is investigated.

Download Full-text

Steady-state correlations of two atoms interacting with a reservoir

Quantum Information and Computation ◽

10.26421/qic12.3-4-4 ◽

2012 ◽

Vol 12 (3&4) ◽

pp. 231-252

Author(s):

Luis Octavio Castanos

Keyword(s):

Electromagnetic Field ◽

Steady State ◽

Master Equation ◽

Field Intensity ◽

Mixed State ◽

Laser Field ◽

Quantum Discord ◽

Energy Levels ◽

High Laser ◽

X State

We consider two two-level atoms fixed at different positions, driven by a resonant monochromatic laser field, and interacting collectively with the quantum electromagnetic field. A Born-Markov-secular master equation is used to describe the dynamics of the two atoms and the steady-state is obtained analytically for a configuration of the atoms. The steady-state populations of the energy levels of the free atoms, entanglement, quantum and geometric discords and degree of mixedness are calculated analytically as a function of the laser field intensity and the distance between the two atoms. It is found that there is a possibility of considerable steady-state entanglement and left/right quantum discord and that these can be controlled either by increasing/decreasing the intensity of the laser field or by increasing/decreasing the distance between atoms. It is shown that the system of two atoms can be prepared in a separable mixed state with non-zero quantum discord that turns into an $X$-state for high laser field intensities. The behavior and relationships between the different correlations are studied and several limiting cases are investigated.

Download Full-text

The master equation for a two-level atom in a laser field with squeezing-like terms

Optics Communications ◽

10.1016/j.optcom.2008.10.073 ◽

2009 ◽

Vol 282 (5) ◽

pp. 914-921 ◽

Cited By ~ 10

Author(s):

A.-S.F. Obada ◽

S. Abdel-Khalek ◽

M.M.A. Ahmed ◽

D.A.M. Abo-Kahla

Keyword(s):

Master Equation ◽

Laser Field ◽

Level Atom

Download Full-text

FORCES ON A THREE-LEVEL ATOM INDUCED BY TWO LASER BEAMS

International Journal of Modern Physics B ◽

10.1142/s0217979206035801 ◽

2006 ◽

Vol 20 (32) ◽

pp. 5473-5482

Author(s):

V. V. PARANJAPE ◽

P. V. PANAT

Keyword(s):

Master Equation ◽

Laser Beams ◽

Optical Forces ◽

Present Formulation ◽

Coherent Light ◽

Level Atom ◽

Light Beams ◽

Analytical Expressions

We present formulation of optical forces acting on a three-level atom coupled to two coherent light beams. Analytical expressions for the force are obtained by using the master equation. All three configurations: Raman, V-shaped and cascade are used for the analysis. The dipolar force is obtained numerically as a function of detuning.

Download Full-text

COOPERATIVE EFFECTS ON OPTICAL FORCES — DICKE'S BULLET

International Journal of Modern Physics B ◽

10.1142/s0217979202013043 ◽

2002 ◽

Vol 16 (25) ◽

pp. 3787-3795 ◽

Cited By ~ 2

Author(s):

P. V. PANAT ◽

S. V. LAWANDE

Keyword(s):

Angular Momentum ◽

Radiation Field ◽

Bessel Beam ◽

Coherent Radiation ◽

Optical Forces ◽

Radiation Wavelength ◽

Spatial Profile ◽

Cooperative Effects

We investigate the cooperative effects on optical forces in a system of N two level atoms confined to a volume of dimension less than λ3, where λ is radiation wavelength and driven by a coherent radiation field with a spatial profile like Laguerre–Gaussian or ideal Bessel beam. We show a dramatic enhancement on optical forces as well as on the angular momentum imparted to the atom by a factor of N2.

Download Full-text