I. N. Adamenko

Transmission and reflection of phonons and rotons at the superfluid helium-solid interface

We solve the problem of the transmission and reflection of phonons and rotons at the interface between superfluid helium and a solid for all angles of incidence and in both directions. A consistent solution of the problem is presented, which allows us to rigorously describe the simultaneous creation of phonons and

Three-phonon relaxation in isotropic and anisotropic phonon systems of liquid helium at different pressures

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Creation of high-energy phonons by four-phonon processes in anisotropic phonon systems of HeII

and

Longitudinal evolution of a phonon pulse in liquid 4He

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Pressure of thermal excitations in superfluid helium

rotons in helium by either a phonon from the solid or a helium quasiparticle incident on the interface. The interaction of all

The decay of one phonon into three in superfluid helium

\text{He}\text{ }\text{II}

Four- and three-phonon scattering in isotropic superfluid helium

quasiparticles with the interface, as well as their transmission, reflection, and conversion into each other, is described in a unified way. The angles of propagation and the probabilities of creating quasiparticles are obtained for all of the cases. The Andreev reflection of helium phonons and rotons is predicted. Energy flows through the interface due to phonons and

Thermodynamics of anisotropic phonon systems in superfluid helium

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Quasiequilibrium distribution function of anisotropic phonon systems and the interaction of pulses of low-energy phonons in superfluid helium

and

Creation and decay of high-energy phonons in anisotropic systems of low-energy phonons in superfluid helium

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