Induced-dichroism-excited atomic line filter at 532 nm

Abstract

The operation of a narrow-linewidth optical f ilter based on the 4P((1/2)) ? 8S((1/2)) excited-state transition in potassium vapor is reported. The 4P((1/2)) state is excited by a circularly polarized, 769.9-nm, 10-ns pulse from a dye laser. A linearly polarized, time-sequenced, and spatially overlapped probe pulse at 532.33 nm completes the transition to the 8S((1/2)) state. The peak filter transmission is ~40% with a bandwidth of less than 4 GHz. Corroborative experimental results suggest that the rotation of probe-pulse polarization by an induced circular birefringence is the dominant mechanism behind the filter operation.

Theory and experiment for atomic optical filter based on optical anisotropy in rubidium

“…However, higher pump intensity can pump a broader velocity group of atoms resulting from power broadening, causing an incremental increase of the transmission. In the theoretical prediction, the peak transmission becomes saturated when the pump intensity almost pumps 50% population of the ground-state into the excited state, which is also demonstrated in [14].…”

“…The peak transmission efficiency increases as the pump intensity does at the expenses of a broader filter bandwidth. Using a strong pulse pump field, the peak transmission of the filter can be more than 40%, while the filter bandwidth is over several gigahertz [14]. In our theoretical prediction, the extremum of peak transmission for the filter based on optical pumping can reach to 50%.…”

“…For example, Faraday anomalous dispersion optical filter (FADOF) based on Faraday effect has been extensively studied [5][6][7][8][9][10][11] and has been utilized to many practical applications, such as laser communication [12] and lidar [13], with their merits of high transmission, narrow-bandwidth and excellent out-of-band rejection. In addition, atomic optical filters based on optical anisotropy induced by another selective-polarized pumping beam were preliminarily experimentally demonstrated [14][15][16], however, the theoretical model and the analysis of filter characteristics for this category of filter have not been reported.…”

Study of the effect of repump laser on atomic line filter

“…Different types of optical filters have been reported earlier; they include Faraday anomalous dispersion optical filter [13][14][15], induced dichroism excited atomic line filter (IDEALF) [16][17][18], etc. Recently, Cerè et al [19] reported on using velocity-selective optical pumping signal for executing an atomic filter on resonance.…”

Laser-induced dispersion optical filter at 532 nm

“…Laser-induced dispersion optical filter (LIDOF) was first described and experimentally studied by R.I.Billmers et al in1995 [1] .The LIDOF also performs the optical filtering by making the polarization plane of the signal beam rotated as the same as Faraday anomalous dispersion optical filter (FADOF). But the reason for rotation of polarization plane in this filter is circular birefringence produced by induced dichroism, which causes excited-state atoms have different absorption to left and right circularly polarized beams respectively and makes polarization plane rotated.…”