1. Increasing quantum limited sensitivity of
interferometers using electromagnetically
induced transparency
Hunter Rew
Advised by Dr. Eugeniy Mikhailov
2. What to expect
● Introduction
○ Gravitational wave detection
○ Increasing sensitivity
○ Electromagnetically induced transparency
● Simulation methods and results
● Experimental methods and results
● Conclusions
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3. Gravitational Waves
Gravitational waves (GWs) are a
prediction of general relativity.
GWs contract space in one
direction while expanding it in
transverse directions
Copyright: [NASA]
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4. Interferometric Gravitational Wave Detectors
GW changes lengths of arms
relative to each other, creating
a phase shift in the light
GW interferometers such as
Advanced LIGO are
approaching the standard
quantum limit
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6. Noise in LIGO
Noise sources within LIGO
are frequency dependent
6[Nature Photonics 7, 613–619 (2013) doi:10.1038/nphoton.2013.177]
7. Electromagnetically Induced Transparency
Opaque media become transparent when optical fields are applied at the
transitions of hyperfine ground states. A dark state is produced from the
superposition of these states.
● Produce narrow linewidths
● Near 100% transmission
● Tunable
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11. Methods (cont.)
Simulations varied the following parameters:
● Drive Rabi frequency (Ωd
) from 17 to 25 KHz
● 2 photon detuning ( ) with a range based on the given drive
● Time from 0 to 0.1 s
● Media length from 0 to 2 cm
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12. Methods (cont.)
Constants:
● Probe Rabi frequency (Ωp
) of 0.1 Hz
● Excited state decay (γ) of 6 MHz
● Ground state decay (γbc
) of 1 Hz
● Particle density of 1015
particles per m3
● Transitions at 794.7 nm
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19. Experimental parameters
● Rubidium cell is roughly 1.5 cm in diameter and 1 cm in length
○ Anti-relaxation coating
● Drive and probe intensities are roughly equal
○ Rabi frequencies from 5 to 30 MHz
● Cell temperatures from 35 to 75 Celsius
○ Particle concentrations from 3 x 1010
to 9 x 1011
● Beam waists from full to 0.8ω0
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20. Analysis of experimental data
Data is fit to a generalized
Lorentzian
A is the contrast
γ is the linewidth / 2
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29. Conclusions and future work
● Best contrast: 3.9%
● Best linewidth: 202 Hz
● Experiment and simulation
agree (mostly)
● Low temperatures show
promise
● Low drive intensities show
promise
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