Polarization rotation of photon echo at J = 0 <->1 transition in magnetic field

摘要

Detailed experimental analysis of photon echo polarization in a longitudinal magnetic field is performed for the first time at the simplest quantum transition J = 1<-> J = 0 for which the non-Faraday rotation of photon echo polarization plane was predicted. The echo was generated at the intercombination transition (6s6p){sup}3Pi →(6s{sup}2){sup}1So of 174{sup left}Yb by two resonant laser pulses of linear (parallel or mutually orthogonal) polarization, and the angled echo optical scheme was applied for the detection. At the magnetic field strength B ≤5 G the photon echo has polarization very close to linear one; its polarization plane rotates around magnetic field vector, and photon echo polarization components and integral echo power oscillate versus B from its maximum value to zero, in agreement with theory. At a stronger magnetic field B ～ 40 G photon echo power oscillations disappear, no preferable orientation of polarization vector is observed; the fluctuations of exciting radiation spectrum are supposed to be responsible for this "non-polarized" echo. Photon echo power in dependence on azimuthal angle at high magnetic field B ≈ 40 G. Solid line represents cubic parametric interpolation of B-spline type.