Adamenko, I.N.; Nemchenko, K.E.; Slipko, V.A.; Wyatt, A.F.G.
(Физика низких температур, 2007)
We discuss a number of unusual phenomena, which have been discovered recently in anisotropic
quasiparticle systems in superfluid ⁴He. These include the creation of high-energy phonons by a pulse of
low-energy phonons, ...