Please use this identifier to cite or link to this item: http://hdl.handle.net/11189/6256
Title: On the non-linear spectroscopy including saturated absorption and four-wave mixing in two and multi-level atoms: a computational study
Authors: Patel, M 
de Jager, Gerhard 
Nkosi, Z 
Wyngaard, A 
Govender, K 
Keywords: Non-linear spectroscopy;Saturated absorption;Multi-level atoms
Issue Date: 2017
Publisher: IOP Publishing
Journal: Journal of Physics: Conference Series 
Abstract: In this paper we report on the study of two and multi-level atoms interacting with multiple laser beams. The semi-classical approach is used to describe the system in which the atoms are treated quantum mechanically via the density matrix operator, while the laser beams are treated classically using Maxwells equations. We present results of a two level atom interacting with single and multiple laser beams and demonstrate Rabi oscillations between the levels. The effects of laser modulation on the dynamics of the atom (atomic populations and coherences) are examined by solving the optical Bloch equations. Plots of the density matrix elements as a function of time are presented for various parameters such as laser intensity, detuning, modulation etc. In addition, phase-space plots and Fourier analysis of the density matrix elements are provided. The atomic polarization, estimated from the coherence terms of the density matrix elements, is used in the numerical solution of Maxwells equations to determine the behaviour of the laser beams as they propagate through the atomic ensemble. The effects of saturation and hole-burning are demonstrated in the case of two counter propagating beams with one being a strong beam and the other being very weak. The above work is extended to include four-wave mixing in four level atoms in a diamond configuration. Two co-propagating beams of different wavelengths drive the atoms from a ground state |1i to an excited state |3i via an intermediate state |2i. The atoms then move back to the ground state via another intermediate state |4i, resulting in the generation of two additional correlated photon beams. The characteristics of these additional photons are studied.
URI: http://hdl.handle.net/11189/6256
ISSN: 1742-6588
Appears in Collections:HWSci - Journal Articles (DHET subsidised)

Files in This Item:
File Description SizeFormat 
On the non-linear spectroscopy including saturated.pdfMain article1.92 MBAdobe PDFView/Open
Show full item record

Page view(s)

10
checked on Jul 20, 2018

Google ScholarTM

Check


This item is licensed under a Creative Commons License Creative Commons