fElectron Contribution to the Change of Electronic Structure inCeRu2Si2with Temperature: A Compton Scattering Study

Abstract

High resolution Compton profiles have been measured in the single crystal of CeRu(2)Si(2) above and below the Kondo temperature to elucidate the change of the Ce-4f electron from localized to itinerant states. Two-dimensional electron occupation number densities projected on the first Brillouin zone, which are obtained after a series of analyses, clearly specify the difference between itinerant and localized states. The contribution of Ce-4f electrons to the electronic structure is discussed by contrast with a band calculation.

Fermi Surface Properties, Metamagnetic Transition and Quantum Phase Transition of CeRu2Si2 and Its Alloys Probed by the dHvA Effect

“…The present observation for temperature variation is in contrast with those in the heavy fermion compounds where no observation of an intermediate Fermi surface between those corresponding to the large Fermi surface and the small Fermi surface has been reported from ARPES measurements. [112][113][114][115]184 It is also reported in UPd 2 Al 3 that the Fermi surface changes rather abruptly between 40 K and 60 K. 184 Then, the continuous change in the observed frequency may not directly correspond to a continuous change of the Fermi edge with temperature. But it could be explained by the two Fermi edges corresponding to the small and large Fermi surfaces and the former one diminishes while the latter one grows with decreasing temperature as expected in the case of compounds.…”

Anharmonic Thermal Oscillations of the Electron Momentum Distribution in Lithium Fluoride

“…Among other investigations, Compton scattering has thus been fruitfully applied to unveil the temperature dependence of the configurational enthalpy in ice, spin, and magnetic moments of several crystals and shape memory alloys, the electron localization state in CeRu 2 Si 2 below and above the Kondo temperature, etc. [13][14][15][16][17][18][19].…”

Point-Contact Spectroscopy of Heavy Fermion Compound CeRu2Si2 in Magnetic Field

“…The magnetization process for the c-axis at low temperature exhibits a metamagnetic-like transition at the field of H M ∼ 7.7 T. Accompanying with this metamagnetic-like transition, a large change of the effective mass of conduction electrons, which derived from the electronic specific heat coefficient and the coefficient of T 2 contribution of the electrical resistivity, was observed. In order to reveal the mechanism of the metamagnetic-like transition, studies by using various experimental methods as well as theoretically have been carried out [1][2][3][4][5][6][7][8][9][10][11][12][13].…”