monochromatic atomic beam

isotope separation

thin film deposition of TiO2

thin film deposition of BN


radially polarized laser beam (generation)

radially polarized laser beam (calculation) 



Improvement of light induced drift using wavelength tunable semiconductor lasers


Light induced drift (LID) is a phenomenon observable under velocity selective excitation of atoms in specific buffer gas as a result of difference of diffusion cross section between ground an excited states of atom.  When the isotope shift in light absorption is larger than laser spectral width, the LID can be used for the isotope separation.  We are trying to improve the efficiency of the isotope separation by the LID using wavelength tunable semiconductor lasers.  We have found that the efficiency can be greatly improved by reducing optical pumping using an additional semiconductor laser.  We are developing a laser system1) for and observing the LID2).


1) K. Sasaki, T. Yoneyama, T. Nakamura, S. Sato and A. Takeyama, Semiconductor laser based, injection locking maintaining broad linewidth generated by a direct current modulation of a master laser, Rev. Sci. Inst. 77 (2006) 096107. link

2) M. Okamoto, T. Nakamura, and S. Sato, Observation of light-induced drift effect of Rubidium by using two diode lasers for pumping and repumping, Materials Transactions 49, 2632 (2008). link