Density and spin-density excitations in normal-liquid He
نویسندگان
چکیده
In bulk Fermi liquids such as liquid He and nuclear matter the quasiparticle effective mass is enhanced at the Fermi surface and reduces to the bare mass far from the Fermi surface. We incorporate this central physical feature into the density and spin-density dynamics of normal-liquid He and obtain good agreement with recent high-resolution neutron-scattering experiments. Existing theories up to this time using quadratic quasiparticle dispersion do not reproduce experiment. @S0163-1829~97!05010-8#
منابع مشابه
Fluctuating spin density waves in metals
Recent work has used a U(1) gauge theory to describe the physics of Fermi pockets in the presence of fluctuating spin density wave order. We generalize this theory to an arbitrary band structure and ordering wavevector. The transition to the large Fermi surface state, without pockets induced by local spin density wave order, is described by embedding the U(1) gauge theory in a SU(2) gauge theor...
متن کاملElementary electronic excitations in one-dimensional continuum and lattice systems
We systematically investigate the mode dispersion and spectral weight of the elementary excitation spectra in one-dimensional continuum and lattice electron systems by using the RPA, the Luttinger liquid model, and the Hubbard model. Both charge and spin excitations are studied in detail and compared among the theoretical models. For the lattice Hubbard model we use both Bethe-ansatz equations ...
متن کامل1 Elementary electronic excitations in one - dimensional continuum and lattice systems
We systematically investigate the mode dispersion and spectral weight of the elementary excitation spectra in one-dimensional continuum and lattice electron systems by using the RPA, the Luttinger liquid model, and the Hub-bard model. Both charge and spin excitations are studied in details and compared among the theoretical models. For the lattice Hubbard model we use both Bethe-ansatz equation...
متن کاملExcitations of superfluid He in porous media: Aerogel and Vycor
We present precision neutron scattering measurements of the dynamic structure factor S(Q ,v) and the elementary excitations of liquid He immersed in aerogel and Vycor. In both porous media, liquid He supports two-dimensional ~2D! layer modes at wave vectors in the roton region that propagate in the liquid layers adjacent to the media walls. The layer modes have a rotonlike energy dispersion rel...
متن کاملExcitations of super uid He in porous media: aerogel and Vycor
We present precision neutron scattering measurements of the dynamic structure factor, S(Q;!), and the elementary excitations of liquid He immersed in aerogel and Vycor. In both porous media, liquid He supports two-dimensional (2D) layer modes at wavevectors in the roton region that propagate in the liquid layers adjacent to the media walls. The layer modes have a roton-like energy dispersion re...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 1997