Related Experiment Video
Updated: Apr 20, 2026
05:39
Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
10.5K
Quantum critical fluctuations in the heavy fermion compound Ce(Ni0.935Pd0.065)₂Ge₂
C H Wang1, L Poudel, A E Taylor
1Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA. University of California, Irvine, CA 92697, USA.
Summary
This study investigates spin fluctuations in a heavy fermion compound near an antiferromagnetic quantum critical point. Alloy disorder may explain deviations from expected quantum critical point behavior.
Area of Science:
- Condensed Matter Physics
- Quantum Critical Phenomena
- Materials Science
Background:
- Heavy fermion compounds exhibit complex magnetic behavior.
- Quantum critical points (QCPs) are fascinating states where magnetic order is suppressed by quantum fluctuations.
- Understanding QCPs is crucial for developing new materials with exotic electronic properties.
Purpose of the Study:
- To investigate spin fluctuations in the heavy fermion compound Ce(Ni0.935Pd0.065)2Ge2.
- To study the behavior of this material near an antiferromagnetic (AF) quantum critical point (QCP).
- To explore the influence of alloy disorder on quantum critical phenomena.
Main Methods:
- Single crystal growth of Ce(Ni0.935Pd0.065)2Ge2.
- Measurements of electric resistivity and specific heat.
- Magnetic susceptibility and inelastic neutron scattering experiments.
Main Results:
- Observed power law behavior in resistivity and specific heat at low temperatures (T ≤ 1 K), consistent with a 3D itinerant AF QCP.
- Observed logarithmic temperature dependence in susceptibility and specific heat, and linear resistivity at intermediate temperatures (2 K ≤ T ≤ 10 K).
- Spin fluctuation correlation length, time, and staggered susceptibility remained finite, deviating from expected QCP divergence.
Conclusions:
- The material exhibits non-Fermi liquid behavior, indicative of proximity to a QCP.
- Deviations from expected QCP scaling suggest the significant role of alloy disorder.
- Alloy disorder may suppress the development of long-range correlations and influence the nature of quantum criticality.
Related Concept Videos
01:12Fermi Level Dynamics
1.1K
The vacuum level denotes the energy threshold required for an electron to escape from a material surface. It is usually positioned above the conduction band of a semiconductor and acts as a benchmark for comparing electron energies within various materials.
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
1.1K
01:18Fermi Level
2.6K
The Fermi-Dirac function is represented by an S-shaped curve indicating the probability of an energy state being occupied by an electron at a given temperature. The Fermi level is the energy level at which there is a fifty percent chance of finding an electron, and it is positioned between the lower-energy valence band and the higher-energy conduction band.
At absolute zero temperature, electrons fill all energy states up to the Fermi level, leaving upper states empty. As the temperature rises,...
At absolute zero temperature, electrons fill all energy states up to the Fermi level, leaving upper states empty. As the temperature rises,...
2.6K
03:26Electron Configuration of Multielectron Atoms
68.8K
The alkali metal sodium (atomic number 11) has one more electron than the neon atom. This electron must go into the lowest-energy subshell available, the 3s orbital, giving a 1s22s22p63s1 configuration. The electrons occupying the outermost shell orbital(s) (highest value of n) are called valence electrons, and those occupying the inner shell orbitals are called core electrons. Since the core electron shells correspond to noble gas electron configurations, we can abbreviate electron...
68.8K
01:26Imperfections in Crystal Structure: Stoichiometric Point Defects
101
Schottky defects arise when some lattice points in a crystal, such as those in NaCl, remain unoccupied, creating lattice vacancies without disturbing the overall electrical neutrality of the crystal. This defect is common in ionic crystals where the positive and negative ions are similar in size, as seen in sodium chloride and cesium chloride. The presence of Schottky defects enables the crystal to conduct electricity to a small extent through an ionic mechanism. Electric fields cause nearby...
101
02:42Valence Bond Theory
11.9K
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
11.9K
02:54Trends in Lattice Energy: Ion Size and Charge
27.8K
An ionic compound is stable because of the electrostatic attraction between its positive and negative ions. The lattice energy of a compound is a measure of the strength of this attraction. The lattice energy (ΔHlattice) of an ionic compound is defined as the energy required to separate one mole of the solid into its component gaseous ions. For the ionic solid sodium chloride, the lattice energy is the enthalpy change of the process:
27.8K