Influence of thermal effects on the two-photon absorption line profile of ions captured in a trap

An investigation is made of the two-photon absorption line profile in a standing-wave field for particles trapped in an oscillator potential at right angles to the optical beam. It is found that this profile is an equidistant lattice of resonances if the oscillation frequency and the amplitude of the ion thermal oscillations are greater than the homogeneous line width and the size of the optical beam, respectively. Allowance for the thermal quadratic Doppler and Stark effects results in broadening of each resonance and changes its profile. A new method of eliminating thermal broadening of the spectral components of the line profile is discussed