16 citations · 70 across the 7 of their papers we have counts for
6 papers
Quasiparticles, coherence and nonlinearity: exact simulations of RF-spectroscopy of strongly interacting one-dimensional Fermi gases
M. J. Leskinen, V. Apaja, J. Kajala +1
We consider RF-spectroscopy of ultracold Fermi gases by exact simulations of the many-body state and the coherent dynamics in one dimension. Deviations from the linear response sum…
Structure of metastable 2D liquid helium
V. Apaja, M. Saarela
We present diffusion Monte Carlo (DMC) results on a new metastable, superfluid phase above the crystal ground state in two-dimensional 4He at densities > 0.065 1/A^2. The state is…
Monte Carlo simulation of boson lattices
Vesa Apaja, Olav F. Syljuasen
Boson lattices are theoretically well described by the Hubbard model. The basic model and its variants can be effectively simulated using Monte Carlo techniques. We describe two ne…
Many-body aspects of positron annihilation in the electron gas
V. Apaja, S. Denk, E. Krotscheck
We investigate positron annihilation in electron liquid as a case study for many-body theory, in particular the optimized Fermi Hypernetted Chain (FHNC-EL) method. We examine sever…
Layer- and bulk roton excitations of 4He in porous media
V. Apaja, E. Krotscheck
We examine the energetics of bulk and layer-roton excitations of 4He in various porous medial such as aerogel, Geltech, or Vycor, in order to find out what conclusions can be drawn…
Excitations in confined helium
V. Apaja, E. Krotscheck
We design models for helium in matrices like aerogel, Vycor or Geltech from a manifestly microscopic point of view. For that purpose, we calculate the dynamic structure function of…