by Alexander Rietzler
Abstract:
In this thesis, we describe the main steps for the production and stabilization of the laser light used to cool erbium atoms in a magneto-optical trap (MOT). The line that we use for the MOT has a narrow-line character with a 190-kHz linewidth and has a wavelength of 583 nm. To generate the light at 583 nm, we use a dye laser, operated with Rhodamine 6G. The laser light from the dye laser has a linewidth of about 1 MHz and a frequency drift of about 100 MHz/h. For MOT operation, we need to reduce the laser linewidth and to stabilize the laser on the resonance frequency for the different Er isotopes. For this purpose, we use a pre-locking cavity, which narrows the linewidth down to 45 kHz and we build a ultra low expansion (ULE) cavity for long-term frequency stability. A special and convenient feature of our stabilization scheme is that it allows locking of the cooling light on the atomic transition of each Er isotope in a very straightforward manner – it can in fact bridge the isotope shifts, corresponding to several GHz. The part of our locking setup that is responsible for long-term frequency stability is based on the Pound-Drever-Hall locking technique in combination with a home-build ULE cavity. This cavity is made of ultra low expansion glass, which we cool down to the zero-expansion temperature. At this temperature, the thermal expansion of the cavity is minimized. By stabilizing the laser to the ULE cavity, we reduce the long-term drift to 0.16 Hz/s. Using this light, we cooled down the five most abundant erbium isotopes to 15μK in the MOT, and recently we achieved the first BEC of erbium atoms.
Reference:
Narrow-Line Cooling Light for a Magneto-Optical Trap of Erbium Atoms,
Alexander Rietzler,
Master’s Thesis, 2012.
Alexander Rietzler,
Master’s Thesis, 2012.
Bibtex Entry:
@article{RietzlerMSc,
title = {Narrow-Line Cooling Light for a Magneto-Optical Trap of Erbium Atoms},
author = {Rietzler, Alexander},
journal = {Master's Thesis},
year = {2012},
month = {Oct},
abstract = {In this thesis, we describe the main steps for the production and stabilization
of the laser light used to cool erbium atoms in a magneto-optical trap (MOT). The
line that we use for the MOT has a narrow-line character with a 190-kHz linewidth
and has a wavelength of 583 nm. To generate the light at 583 nm, we use a dye laser,
operated with Rhodamine 6G. The laser light from the dye laser has a linewidth of
about 1 MHz and a frequency drift of about 100 MHz/h. For MOT operation, we need to
reduce the laser linewidth and to stabilize the laser on the resonance frequency for
the different Er isotopes. For this purpose, we use a pre-locking cavity, which narrows
the linewidth down to 45 kHz and we build a ultra low expansion (ULE) cavity for long-term
frequency stability. A special and convenient feature of our stabilization scheme is that
it allows locking of the cooling light on the atomic transition of each Er isotope in a
very straightforward manner - it can in fact bridge the isotope shifts, corresponding to
several GHz. The part of our locking setup that is responsible for long-term frequency
stability is based on the Pound-Drever-Hall locking technique in combination with a home-build
ULE cavity. This cavity is made of ultra low expansion glass, which we cool down to the zero-expansion
temperature. At this temperature, the thermal expansion of the cavity is minimized. By
stabilizing the laser to the ULE cavity, we reduce the long-term drift to 0.16 Hz/s.
Using this light, we cooled down the five most abundant erbium isotopes to 15μK in the
MOT, and recently we achieved the first BEC of erbium atoms.},
url = {http://www.erbium.at/FF/wp-content/uploads/2015/10/master_alexander_rietzler.pdf},
}