Optical irradiation device for the polarization of alkali atoms and a device for the hyperpolarization of noble gases
View Patent ↗An optical irradiation device for the polarization of alkali metal atoms for the hyperpolarization of noble gases by spin exchange includes at least one semiconductor laser device which can generate laser light which, with regard to its wavelength, is suitable for the polarization of the alkali metal atoms. A polarizer effects circular polarization of the laser light generated by the semiconductor laser device. A device for introducing the laser light into a working region in which the alkali metal atoms to be polarized can be present, and a device for defining a wavelength of the laser light, which can couple part of the laser light back into the semiconductor laser device in order thereby to define the wavelength of the laser light at a predetermined wavelength or a predetermined wavelength range.
1. An optical irradiation device for polarizing alkali atoms, comprising:
at least one semiconductor laser device configured to generate laser light that is suitable, with respect to a wavelength thereof, for polarizing alkali atoms;
a polarizer for circular polarization of the laser light generated by said at least one semiconductor laser device;
means for introducing the laser light into a working area configured to hold therein the alkali atoms to be polarized;
means for defining the wavelength of the laser light and for coupling back a portion of the laser light into the semiconductor laser device for defining the wavelength of the laser light at a predetermined wavelength or a predetermined wavelength range; and
a homogenizer that homogenizes the laser light, the homogenizer being disposed downstream in the propagation direction of the laser light from said means for defining the wavelength.
2. The irradiation device according to claim 1 , wherein said means for defining the wavelength of the laser light are in the form of gratings.
3. The irradiation device according to claim 2 , wherein said gratings are Bragg gratings or Littrow gratings.
4. The irradiation device according to claim 1 , wherein said homogenizer is a two-stage homogenizer.
5. The irradiation device according to claim 1 , wherein said homogenizer is configured to homogenize the laser light with respect to two mutually perpendicular directions.
6. The irradiation device according to claim 1 , wherein said homogenizer comprises at least one optically functional interface with a lens array.
7. The irradiation device according to claim 1 , wherein said homogenizer comprises at least one optically functional interface with a cylindrical lens array.
8. The irradiation device according to claim 1 , wherein said means for introducing the laser light into a working area comprise at least one lens.
9. The irradiation device according to claim 1 , which further comprises a telescopic unit disposed between said at least one semiconductor laser device and the working area for holding the alkali atoms.
10. A device for hyperpolarizing noble gases, comprising:
an optical irradiation device for polarizing alkali atoms according to claim 1 ; and
means for hyperpolarizing a noble gas by spin exchange with the polarized alkali atoms polarized by said optical irradiation device.