Phase Diagram of the First-Order Vortex-Core Transition in SuperfluidHe3-B

Vortices with spontaneously broken axisymmetry inB3

“…(Received 18 October 1985) This paper reports the discovery of a new breaking of symmetry of the quantized vortex lines in superfluid 3 He-J9: Vortices with broken axisymmetry are found to be energetically more favorable than any of the axisymmetric ones in the weak-coupling limit. On the basis of our extensive numerical minimization of the vortex free-energy functional, we identify the vortices occurring in rotating 3 He-£ at low pressures as v vortices having-in addition to broken space parity P-also broken axisymmetry Q with the nonaxisymmetry quantum number 1^1 = 2, and with superfluid core in the axiplanar state.…”

“…On the basis of our extensive numerical minimization of the vortex free-energy functional, we identify the vortices occurring in rotating 3 He-£ at low pressures as v vortices having-in addition to broken space parity P-also broken axisymmetry Q with the nonaxisymmetry quantum number 1^1 = 2, and with superfluid core in the axiplanar state.…”

“…PACS numbers: 67.50.Fi Core structures of quantized vortex lines in superfluid 3 He-2? were expected to be no more interesting than those in He II, until a spontaneous phase transition was observed 1 in the rotating bulk B phase.…”

“…2 The phase diagram of the vortex-core transition has been measured with both NMR and hydrodynamic techniques. 3 At high pressures the core-transition temperature follows roughly parallel to the A -B transition until the polycritical pressure, where it curves horizontally toward T Much work has been devoted to the effort of identifying the vortices associated with this unexpected transition. It was soon realized that because of the complicated "vacuum" state in superfluid 3 He-2?, with several symmetries simultaneously broken, it is possible to have five singly quantized vortex lines with different internal symmetries.…”

“…8 (Note that axisymmetry tends to be broken, as a rule, for both singular and continuous vortices in 3 He-v4.) We present the first results of our extensive numerical search for nonaxisymmetric instabilities of vortices in 3 He-2?. We found that a certain nonaxisymmetric v vortex has an energy lower (by an amount nearly equal to the energy difference between the axisymmetric o and v vortices) than that of the axisymmetric v vortex.…”