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

2009 ◽  
Vol 282 (5) ◽  
pp. 914-921 ◽  
Author(s):  
A.-S.F. Obada ◽  
S. Abdel-Khalek ◽  
M.M.A. Ahmed ◽  
D.A.M. Abo-Kahla
2000 ◽  
Vol 14 (17n18) ◽  
pp. 631-637 ◽  
Author(s):  
S. V. LAWANDE ◽  
P. V. PANAT

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.


2012 ◽  
Vol 12 (3&4) ◽  
pp. 231-252
Author(s):  
Luis Octavio Castanos

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.


1999 ◽  
Vol 46 (5) ◽  
pp. 743-754 ◽  
Author(s):  
Pasquale Caldara ◽  
Emilio Fiordilino

2001 ◽  
Vol 91 (3) ◽  
pp. 470-476 ◽  
Author(s):  
A. Kowalewska-Kudłaszyk ◽  
R. Tanaś

2019 ◽  
Vol 34 (17) ◽  
pp. 1950099
Author(s):  
Zhiming Huang ◽  
Xiaobin Wang ◽  
Yiyong Ye ◽  
Xiaokui Sheng ◽  
Zhenbang Rong ◽  
...  

In this work, we investigate the dynamics of quantum-memory-assisted entropic uncertainty relation for a two-level atom coupled with fluctuating electromagnetic field in the presence of a perfectly reflecting plane boundary. The solution of the master equation that governs the system evolution is derived. We find that entropic uncertainty and mixedness increase to a stable value with evolution time, but quantum correlation reduces to zero with evolution time. That is, the mixedness is positively associated with entropic uncertainty, however, increasing quantum correlation can cause the decrease of the uncertainty. The tightness of entropic uncertainty grows at first and then declines to zero with evolution time. In addition, entropic uncertainty fluctuates to relatively stable values with increasing the atom’s distance from the boundary, especially for short evolution time, which suggests a possible way of testing the vacuum fluctuating and boundary effect. Finally, we propose an effective method to control the uncertainty via quantum weak measurement reversal.


2013 ◽  
Vol 87 (1) ◽  
Author(s):  
Krzysztof Szczygielski ◽  
David Gelbwaser-Klimovsky ◽  
Robert Alicki

2009 ◽  
Vol 388 (18) ◽  
pp. 3961-3968 ◽  
Author(s):  
A.-S.F. Obada ◽  
S. Abdel-Khalek ◽  
M.M.A. Ahmed ◽  
D.A.M. Abo-Kahla

2000 ◽  
Vol 47 (1) ◽  
pp. 11-24 ◽  
Author(s):  
V. O. Chaltykyan ◽  
G. G. Grigoryan ◽  
Y. T. Pashayan
Keyword(s):  

1992 ◽  
Vol 70 (6) ◽  
pp. 427-431 ◽  
Author(s):  
Constantine Mavroyannis

We have considered the induced processes that occur in a driven two-level atom, where a laser photon is absorbed and emitted by the ground and by the excited states of the atom, respectively. In the low-intensity limit of the laser field, the induced spectra arising when a laser photon is absorbed by the ground state of the atom consist of two peaks describing induced-absorption and stimulated-emission processes, respectively, where the former prevails over the latter. Asymmetry of the spectral lines occurs at off-resonance and its extent depends on the detuning of the laser field. The physical, process where a laser photon is emitted by the excited state is the reverse of that arising from the absorption of a laser photon by the ground state of the atom. The former differs from the latter in that the emission of a laser photon by the excited state occurs in the low-frequency regime and that the stimulated-emission process prevails over that of the induced absorption. In this case, amplification of ultrashort pulses is likely to occur without the need of population inversion between the optical transitions. The computed spectra are graphically presented and discussed.


Sign in / Sign up

Export Citation Format

Share Document