Table Of ContentSlow Light, Stopped Light and Guided Light in Hot
Rubidium Vapor Using Off-resonant Interactions
by
Praveen Kumar Vudya Setu
Submitted in Partial Fulfillment
of the
Requirements for the Degree
Doctor of Philosophy
Supervised by
Professor John C. Howell
Department of Physics and Astronomy
Arts, Sciences and Engineering
School of Arts and Sciences
University of Rochester
Rochester, New York
2011
ii
Dedicated to my parents.
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Curriculum Vitae
The author was born in Kurnool, Andhra Pradesh, India on 4 January, 1983.
He attended the Indian Institute of Technology, Kharagpur from 2000 to 2005
and obtained his Bachelor of Science and Master of Science degrees in Physics.
He came to the University of Rochester in the Fall of 2005 for graduate studies
in Physics and received a Master of Arts degree in 2007. He pursued his doctoral
research in atomic physics and quantum optics under the supervision of Professor
John C. Howell.
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Publications
“A double Lorentzian atomic prism”, P. K. Vudyasetu, S. M. Bloch, D. J.
Starling, J. S. Choi and J. C. Howell, Physical Review Letters (Submitted).
“Rapidly reconfigurable slow-light system based on off-resonant Raman ab-
sorption”, P. K. Vudyasetu, R. M. Camacho and J. C. Howell, Physical Review A
82, 053807 (2010).
“Interferometric weak value deflections: Quantum and classical treatments”,
J. C. Howell, D. J. Starling, P. Ben Dixon, P. K. Vudyasetu and A. N. Jordan,
Physical Review A 81, 033813 (2010).
“All Optical Waveguiding in a Coherent Atomic Rubidium Vapor”, P. K.
Vudyasetu, D. J. Starling and J. C. Howell, Physical Review Letters 102, 123602
(2009).
“Four-wave-mixing stopped light in hot atomic rubidium vapour”, R. M. Ca-
macho, P. K. Vudyasetu and J. C. Howell, Nature Photonics 3, 103 (2009).
“Storage and Retrieval of Multimode Transverse Images in Hot Atomic Rubid-
ium Vapor”, P. K. Vudyasetu, R. M. Camacho and J. C. Howell, Physical Review
Letters 100, 123903 (2008).
“Slow-Light Fourier Transform Interferometer”, Z. Shi, R. W. Boyd, R. M.
Camacho, P. K. Vudyasetu and J. C. Howell. Physical Review Letters 99, 240801
(2007).
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Conference Presentations
“Four Wave Mixing (FWM) and Electromagnetically Induced Transparency
(EIT) Based Coherent Image Storage in Hot Atomic Vapors”, P. K. Vudyasetu,
R. M. Camacho, and J. C. Howell, CLEO/QELS 2008 paper: QThB3 (oral pre-
sentation).
“Storage and Retrieval of Images in Hot Atomic Rubidium Vapor”, P. K.
Vudyasetu, R. M. Camacho, and J. C. Howell, Slow and Fast Light (SL) 2008
paper: SWD4 (oral presentation).
“Storing and Manipulating Multimode Transverse Images in Hot Atomic Va-
pors”, P. K. Vudyasetu, D. J. Starling, R. M. Camacho, and J. C. Howell, Laser
Science (LS) 2008 paper: LWD3 (oral presentation).
“Fast Reconfigurable Slow Light System based on Off-resonant Raman Ab-
sorption Scheme”, P. K. Vudyasetu, R. M. Camacho, and J. C. Howell, Frontiers
in Optics (FiO) 2010 paper: FThN5 (oral presentation).
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Acknowledgments
This thesis would not have been possible without the help of many individuals.
First and foremost, I would like to thank my thesis supervisor, Prof. John C.
Howell, for his invaluable guidance through the highs and lows of research over
past 5 years. His enthusiasm for research is infectious and made working in the
laboratory more enjoyable. I cherish his patience and his commitment towards
the progress of my graduate education, which has culminated in this thesis.
I wish to acknowledge my mentors who helped me acquire key research skills.
I would like to thank Michael V. Pack for teaching me optics experimental skills.
He was the man with answers for whatever questions I had, and I learned a great
deal from him about EIT experiments. He was very generous in helping me with
MATLAB and in lending me his books. I enjoyed working with Ryan M. Camacho
on several projects. He taught me the value of good presentations of research ideas
and I have learned a lot about scientific writing from him. He was always there
with help and kind words of wisdom whenever I needed it.
I would like to thank my lab-mates for all their help. I was very fortunate
to work with Curtis J. Broadbent, David J. Starling, Gregory Armstrong, Steven
M. Bloch and Joseph Choi on various projects, who were all fun to work with
and I have learned something or the other from each of them. I, also, had an
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opportunity to work with Zhimin Shi from Prof. Boyd’s group and I thank him
for the discussions on slow light devices.
I would like to extend my sincere gratitude to the university community for
all the warmth and terrific hospitality without which traveling from a far away
country for studies would not have been so wonderful. In particular, I would like
to thank Barbara Warren, Shirley Brignall, Connie Hendricks, Michie Brown and
Ali DeLeon of the Physics department and the staff at the International Services
Office, with whom I have interacted on numerous occasions and they were always
helpful.
I, also, would like to acknowledge the support from the funding agencies
DARPA DSO Slow Light and NSF.
Finally, I would like to thank my family and friends for being supportive and
encouraging. I thank my parents for all the sacrifices they made to ensure my
success.
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Abstract
This thesis presents the applications of some of the coherent processes in a
three-level atomic system, to control spatial and temporal properties of a signal
pulse. We use two Raman absorption resonances in rubidium vapor separated by a
few MHz to achieve a rapidly tunable slow-light system. We control the slow-light
characteristics all-optically by tuning the frequency and power of a coupling beam.
A dual absorption slow-light system is known to cause less pulse broadening than
a single transmission resonance system, and thus, a tunable double absorption
system is advantageous. We use a four-wave mixing process to demonstrate pulse
storage in rubidium vapor for times much greater than the pulse width. We
demonstrate storage of both the temporal and spatial profile of the pulse. We
overcome the diffusion of spatial information during the storage in warm atomic
vapor by storing the Fourier transform of the image instead of an image with a
flat phase. The Raman absorption resonance is also used to control the transverse
refractive index profile of the signal beam. The refractive index of the signal
interacting with a coupling beam in a Raman process is dependent on the coupling
beam intensity. We use a first order Laguerre-Gaussian (LG01) coupling beam
to create a waveguide like transverse refractive index profile. We demonstrate
propagation of a focused signal beam for lengths much greater than the Rayleigh
length. Finally, we demonstrate a dual absorption atomic prism, which is capable
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of spatially separating spectral lines that are 50 MHz apart and which can precisely
measure frequency fluctuations. This simple prism is a valuable spectral filtering
tool for a variety of atomic experiments.
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Table of Contents
Curriculum Vitae iii
Acknowledgments vi
Abstract viii
List of Figures xii
Foreword 1
1 Background 3
1.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.2 Interactions in a Lambda System . . . . . . . . . . . . . . . . . . 7
1.3 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
1.4 Thesis Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
2 Double Raman Absorption Slow Light 27
2.1 Theory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
2.2 Experimental Setup . . . . . . . . . . . . . . . . . . . . . . . . . . 33
