Two-frequency acousto-optic modulator driver to improve the beam pointing stability during intensity ramps
| Autor: | Marco Fattori, Tilman Pfau, T. Koch, Bernd Fröhlich, Bernd Kaltenhäuser, Harald Kübler, Stefan Müller, Thierry Lahaye |
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| Rok vydání: | 2007 |
| Předmět: |
Physics
Diffraction Physics - Instrumentation and Detectors Angular displacement business.industry FOS: Physical sciences Instrumentation and Detectors (physics.ins-det) Displacement (vector) law.invention Intensity (physics) Power (physics) Optics law Ultracold atom Acousto-optic modulator business Instrumentation Beam (structure) Optics (physics.optics) Physics - Optics |
| Zdroj: | The Review of scientific instruments. 78(4) |
| ISSN: | 0034-6748 |
| Popis: | We report on a scheme to improve the pointing stability of the first order beam diffracted by an acousto-optic modulator (AOM). Due to thermal effects inside the crystal, the angular position of the beam can change by as much as 1 mrad when the radio-frequency power in the AOM is reduced to decrease the first order beam intensity. This is done for example to perform forced evaporative cooling in ultracold atom experiments using far-off-resonant optical traps. We solve this problem by driving the AOM with two radio-frequencies $f_1$ and $f_2$. The power of $f_2$ is adjusted relative to the power of $f_1$ to keep the total power constant. Using this, the beam displacement is decreased by a factor of twenty. The method is simple to implement in existing experimental setups, without any modification of the optics. Submitted to Review of Scientific Instruments, 4 pages |
| Databáze: | OpenAIRE |
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