Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Theory of pair breaking by vibrating macroscopic objects in superfluid 3He
AU - Lambert, Colin
PY - 1992/5/2
Y1 - 1992/5/2
N2 - An intuitive picture of dissipation through pair breaking by macroscopic, vibrating objects in an isotropic superfluid is presented, which predicts a critical velocity for direct quasi-particle emission of upsilon(c) = upsilon-0/(1 + alpha), where upsilon-0 is the Landau velocity and alpha characterizes the superfluid backflow. A new intermediate frequency regime is identified, in which pulsed experiments should reveal a hierarchy of critical velocities and sinusoidally vibrating objects will exhibit a crossover to diffusive behaviour. A model of flow through a channel with a rough surface is analyzed, which yields for the instantaneous dissipation Q approximately (upsilon - upsilon(c))5 and Q approximately upsilon-2, at low and high velocities, respectively.
AB - An intuitive picture of dissipation through pair breaking by macroscopic, vibrating objects in an isotropic superfluid is presented, which predicts a critical velocity for direct quasi-particle emission of upsilon(c) = upsilon-0/(1 + alpha), where upsilon-0 is the Landau velocity and alpha characterizes the superfluid backflow. A new intermediate frequency regime is identified, in which pulsed experiments should reveal a hierarchy of critical velocities and sinusoidally vibrating objects will exhibit a crossover to diffusive behaviour. A model of flow through a channel with a rough surface is analyzed, which yields for the instantaneous dissipation Q approximately (upsilon - upsilon(c))5 and Q approximately upsilon-2, at low and high velocities, respectively.
U2 - 10.1016/0921-4526(92)90208-A
DO - 10.1016/0921-4526(92)90208-A
M3 - Journal article
VL - 178
SP - 294
EP - 303
JO - Physica B: Condensed Matter
JF - Physica B: Condensed Matter
SN - 0921-4526
IS - 1-4
ER -