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Development of a Tunable Frequency Shift Filter Using a Praseodymium Doped Y2SiO5-Crystal

Bao, Yupan LU (2016) FYSM31 20152
Department of Physics
Abstract
In this thesis, a tunable frequency shift filter (FSF) with a 1 ~ 2 MHz passband created in a praseodymium doped Y2SiO5-crystal using a special hole burning technique is developed and tested. The FSF is able to shift the frequency of its passband and the light passing through the passband by applying an external electric field, where the frequency shift is proportional to the applied field. Since most of the current frequency shift techniques require the light to be sent in at certain angles (a specific special mode) to the shifter, the $2\pi$ acceptance angle for light of this FSF makes it unique and work more efficiently and less restrictively. The FSF can also slow down the group velocity of the light pulse passing through its passband... (More)
In this thesis, a tunable frequency shift filter (FSF) with a 1 ~ 2 MHz passband created in a praseodymium doped Y2SiO5-crystal using a special hole burning technique is developed and tested. The FSF is able to shift the frequency of its passband and the light passing through the passband by applying an external electric field, where the frequency shift is proportional to the applied field. Since most of the current frequency shift techniques require the light to be sent in at certain angles (a specific special mode) to the shifter, the $2\pi$ acceptance angle for light of this FSF makes it unique and work more efficiently and less restrictively. The FSF can also slow down the group velocity of the light pulse passing through its passband at the order of 10^4 to 10^5. The result of the experimental test of the FSF is quite good. For the FSF with a 1 ~ 2 MHz passband, the light is slowed down to c/10^4 ~ c/10^5. For a 1 MHz FSF, the frequency shift of -4 ~ 4 MHz for both the passband and the light pulse is achieved. The switch-on time for the FSF is around 200 ns limited by the rise time of the electric field. (Less)
Popular Abstract
When you look upon the sky enjoying the beautiful aurora in north of Sweden, are you curious what is happening over there? When you go through the security check and have you luggage scanned, do you wonder how the image is shown? It is all about the light-matter interaction! When light meets matter, happens the story. Different stories happen for different matters, and people are using these stories for different purposes. The story (interaction) happening in this project is between light and rare earth ions that doped in a crystal.

When light passes through the crystal, it will be absorbed (the story will happen) if the frequency of the light coincides with the transition of the rare earth ion (if the light meets the right matter). A... (More)
When you look upon the sky enjoying the beautiful aurora in north of Sweden, are you curious what is happening over there? When you go through the security check and have you luggage scanned, do you wonder how the image is shown? It is all about the light-matter interaction! When light meets matter, happens the story. Different stories happen for different matters, and people are using these stories for different purposes. The story (interaction) happening in this project is between light and rare earth ions that doped in a crystal.

When light passes through the crystal, it will be absorbed (the story will happen) if the frequency of the light coincides with the transition of the rare earth ion (if the light meets the right matter). A bandpass filter will absorb all light within a certain frequency range except for light having the same frequency as its passband. So light with the frequency different from the passband will be filtered out when passing through the filter. This project is about to create a special spectral filter with praseodymium doped Y2SiO5-crystal using the hole burning technique. How is that? Simply speaking, the light with the frequency equal to the passband is pre-sent into the crystal to interact with the 'right ions'. After the interaction, all the 'right ions' will be burnt away, so when the light having the same frequency as the passband comes, there will be no 'right ions' for it to interact with, thus no absorption will happen.

Why do we create such a filter and what is interesting for this filter? Well, with this filter, we could slow down the speed of the light passing in the passband for the order of 10^4 to 10^5! Moreover, by applying an external electric field, the frequency of the passband and the light passing in the passband could be shifted with the frequency shift proportional to the magnitude of the electric field. (Less)
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author
Bao, Yupan LU
supervisor
organization
course
FYSM31 20152
year
type
H2 - Master's Degree (Two Years)
subject
keywords
Ultrasound Optical Tomography (UOT), Off-resonant Slow Light, Filter, Frequency Shifter, Spectral Hole Burning Technique, Rare-earth-ion-doped Crystal
report number
LRAP-512 (2015)
language
English
id
8565724
date added to LUP
2016-01-22 23:58:52
date last changed
2016-01-22 23:58:52
@misc{8565724,
  abstract     = {In this thesis, a tunable frequency shift filter (FSF) with a 1 ~ 2 MHz passband created in a praseodymium doped Y2SiO5-crystal using a special hole burning technique is developed and tested. The FSF is able to shift the frequency of its passband and the light passing through the passband by applying an external electric field, where the frequency shift is proportional to the applied field. Since most of the current frequency shift techniques require the light to be sent in at certain angles (a specific special mode) to the shifter, the $2\pi$ acceptance angle for light of this FSF makes it unique and work more efficiently and less restrictively. The FSF can also slow down the group velocity of the light pulse passing through its passband at the order of 10^4 to 10^5. The result of the experimental test of the FSF is quite good. For the FSF with a 1 ~ 2 MHz passband, the light is slowed down to c/10^4 ~ c/10^5. For a 1 MHz FSF, the frequency shift of -4 ~ 4 MHz for both the passband and the light pulse is achieved. The switch-on time for the FSF is around 200 ns limited by the rise time of the electric field.},
  author       = {Bao, Yupan},
  keyword      = {Ultrasound Optical Tomography (UOT),Off-resonant Slow Light,Filter,Frequency Shifter,Spectral Hole Burning Technique,Rare-earth-ion-doped Crystal},
  language     = {eng},
  note         = {Student Paper},
  title        = {Development of a Tunable Frequency Shift Filter Using a Praseodymium Doped Y2SiO5-Crystal},
  year         = {2016},
}