Physics – Condensed Matter – Strongly Correlated Electrons
Scientific paper
2011-05-11
Physics
Condensed Matter
Strongly Correlated Electrons
7 pages, 6 figures
Scientific paper
$\alpha$-YbAlB$_4$ is the locally isostructural polymorph of $\beta$-YbAlB$_4$, the first example of an Yb-based heavy fermion superconductor which exhibits pronounced non-Fermi-liquid behavior above $T_{\rm c}$. Interestingly, both $\alpha$-YbAlB$_4$ and $\beta$-YbAlB$_4$ have strongly intermediate valence. Our single crystal study of the specific heat, magnetization and resistivity has confirmed the Fermi liquid ground state of $\alpha$-YbAlB$_4$ ~in contrast with the quantum criticality observed in $\beta$-YbAlB$_4$. Both systems exhibit Kondo lattice behavior with the characteristic temperature scale $T^* \sim$ 8 K in addition to a valence fluctuation scale $\sim 200$ K. Below $T^*$, $\alpha$-YbAlB$_4$ a heavy Fermi liquid state with an electronic specific heat coefficient $\gamma\sim$ 130 mJ/mol K$^2$ and a large Wilson ratio more than 7, which indicates ferromagnetic correlation between Yb moments. A large anisotropy in the resistivity suggests that the hybridization between 4$f$ and conduction electrons is much stronger in the $ab$-plane than along the c-axis. The strongly anisotropic hybridization as well as the large Wilson ratio is the key to understand the unusual Kondo lattice behavior and heavy fermion formation in mixed valent compounds.
Karaki Yoshitomo
Kuga Ken'ichi
Matsumoto Yosuke
Nakatsuji Satoru
Tomita Takahiro
No associations
LandOfFree
Anisotropic heavy Fermi-liquid formation in the valence fluctuating $α$-YbAlB$_4$ does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Anisotropic heavy Fermi-liquid formation in the valence fluctuating $α$-YbAlB$_4$, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Anisotropic heavy Fermi-liquid formation in the valence fluctuating $α$-YbAlB$_4$ will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-611186