2009/12/31 by Gabriel Wlazłowski, Gabriel Wlazlowski, Piotr Magierski
Physics and Astronomy · #Atomic and Subatomic Physics Research #Cold Atom Physics and Bose-Einstein Condensates #Condensed matter physics #Mean field theory #Monte Carlo method #Neutron #Neutron scattering #Nuclear matter #Nuclear physics #Nucleon #Path integral Monte Carlo #Path integral formulation #Physics #Propagator #Quantum #Quantum Monte Carlo #Quantum mechanics #Quantum, superfluid, helium dynamics #Quasiparticle #Superconductivity #Superfluidity #cond-mat.stat-mech #nucl-th
paper · pdf · doi:10.1103/physrevc.83.012801
published as Phys.Rev.C83:012801,2011 · 4 pages, 3 figures
openalex publication_date 2011/01/31 · arxiv created 2011/02/01 · arxiv updated 2011/02/21 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We report results of fully nonperturbative, path integral Monte Carlo calculations for dilute neutron matter. The neutron-neutron interaction in the s channel is parameterized by the scattering length and the effective range. We calculate the energy and the chemical potential as a function of temperature at density \ensuremathρ=0.003 fm^\ensuremath-3. The critical temperature Tc for the superfluid-normal phase transition is estimated from the finite size scaling of the condensate fraction. At low temperatures we extract the spectral weight function A(p,\ensuremathω) from the imaginary time propagator using the methods of maximum entropy and singular value decomposition. We determine the quasiparticle spectrum, which can be accurately parameterized by three parameters: an effective mass m*, a mean-field potential U, and a gap \ensuremathΔ. Large values of \ensuremathΔ/Tc indicate that the system is not a BCS-type superfluid at low temperatures.