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تسجيل مستخدم جديدThe influence of the stationary electric field upon the resonance absorption of microwaves in HeII
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The interaction between electromagnetic microwaves (40-200 GHz) and superfluid helium in a stationary electric field has been investigated experimentally. It is found that the narrow line of resonance absorption at the roton frequency is split in the electric field into two symmetric lines. The splitting magnitude increases almost linearly with the electric field, which suggests a linear Stark effect. The results obtained point of orientational polarizability and dipole moment (10^(-34)C*m) in HeII. It is shown that the spectral line profile consists of two parts - a narrow line of resonance absorption (or induced radiation when superfluid stream are generated) and a broad background. The background with agrees well with the latest neutron data for the roton line.
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Based on interrelation between the thermodynamic and electromechanical phenomena in superfluid helium, the explanation of experimentally found features of microwave interaction in the frequency range of 40-200 GHz is given. Due to fast roton-roton an
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