1 / 10

PRELIMINARY DATA ON THE COATING AT THE LIQUID NITROGEN TEMPERATURE

PRELIMINARY DATA ON THE COATING AT THE LIQUID NITROGEN TEMPERATURE. Flavio Travasso Virgo-Perugia Group. Samples. TiO 2 /SiO 2 caoted slab (50 layers evaporated by SILO) (Measured) TiO 2 doped Ta 2 O 5 coated slab (Sputtering by LMA) (Work in progress)

maylin
Télécharger la présentation

PRELIMINARY DATA ON THE COATING AT THE LIQUID NITROGEN TEMPERATURE

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. PRELIMINARY DATA ON THE COATING AT THE LIQUID NITROGEN TEMPERATURE Flavio Travasso Virgo-Perugia Group

  2. Samples • TiO2/SiO2 caoted slab (50 layers evaporated by SILO) (Measured) • TiO2 doped Ta2O5 coated slab (Sputtering by LMA) (Work in progress) • Co doped Ta2O5 coated slab (Sputtering by LMA) (Next months) • Uncoated fused silica (311) slab supplied by LMA (Next months) • Dimension of the slabs: • Silo TiO2/SiO2: 25mm x 25mm x 50 μm with a coating of 5 μm • LMA doped samples: 5mm x 41mm x 104 μm with a coating of about 5 μm

  3. Labview Interface Ni Ni He He He Cu HV Amplifier Clamp tightened using a spring Laser

  4. Preliminary data: TiO2/SiO2 coating • Loss angle vs. Temperature: coated and uncoated sample have a minimum at about 160K • The trend of the coated sample seems to be driven by the behaviour of substrate of fused sillica • Levin model (using a FEM model): we need a good database about the thermal trend of ETiO2 (loss angle of the coating at room temperature is about 10-3) The silica has a peak at the lower temperature…maybe we are seeing the first part (?) CoatedSample UncoatedSample

  5. Preliminary data: TiO2-doped Ta2O5 coating (1) • Coated sample:same trend of the TiO2/SiO2 coated sample • Uncoated sample: work in progress Work done in collaboration with LMA/Virgo laboratory

  6. Preliminary data: TiO2-doped Ta2O5 coating (2) • Increasing of the loss angle decreasing the temperature • The loss angle seems to be frequency dependent: we need much more data to increase the statistics

  7. Temperature hysteresis The dispersion of the data and the value of the ΦTot have a minimum around 160K cooling down and aroud 120K warming up Cool down Warm up

  8. Labview Interface Ni Ni He He He Cu Open problem • Short term upgrade: change present clamp • New suspension system: MIT like • Thermalization of the sample: moving contact, gas of He inside the chamber(?) • Reading of the temperature: twin system • Long term upgrade • Pulse tube: evaluation of the noise Laser

  9. Summary • Trend of the data versus the temperature maybe driven by the substrate • Frequency dependency of the loss angle at temperature lower than 160K • Need to improve the system: short and long term upgrades

More Related