43 citations · 188 across the 24 of their papers we have counts for
13 papers · 1 filter
A Quantitative Solution to the Kondo Lattice Problem
Alex Bretaña, Sean Fayfar, Wouter Montfrooij
Metallic Kondo Lattice systems that have been prepared to exhibit a competition between ordering of magnetic moments and shielding of those moments by the conduction electrons down…
Evidence for magnetic clusters in stoichiometric quantum critical CeRuSi
Alex Bretaña, Sean Fayfar, Wouter Montfrooij
Systems that have been prepared to undergo a second-order phase transition at zero Kelvin, the so-called quantum critical systems, appear to fall into two categories: (chemically)…
Protected percolation: a new universality class pertaining to heavily-doped quantum critical systems
Sean Fayfar, Alex Bretaña, Wouter Montfrooij
We present the results of computer simulations on a class of percolative systems that forms a new universality class. We show the results for the critical exponents for this new cl…
Quantum critical behavior in Ce(FeRu)Ge: the full story
Wouter Montfrooij, Tom Heitmann, Yiming Qiu +7
Systems with embedded magnetic ions that exhibit a competition between magnetic order and disorder down to absolute zero can display unusual low temperature behaviors of the resist…
Identification of the low-energy excitations in a quantum critical system
Tom Heitmann, Jagat Lamsal, Shannon Watson +4
We have identified low-energy magnetic excitations in a doped quantum critical system by means of polarized neutron scattering experiments. The presence of these excitations could…
Comment on "Evidence for a non Fermi liquid phase in Ge-substituted YbRhSi"
John Gaddy, Tom Heitmann, Jagat Lamsal +1
In a recent paper, Custers {\it et al.} \cite{custers} argue for the existence of a new metallic quantum critical phase at 0 K in the Ge-doped heavy-fermion system YbRhSi i…
Magnetic excitations in the spinel compound Li[MnLi]O (x= 0.2, 0.6, 0.8, 1.0): how a classical system can mimic quantum critical scaling
Thomas Heitmann, Alexander Schmets, John Gaddy +4
We present neutron scattering results on the magnetic excitations in the spinel compounds Li[MnLi]O (x= 0.2, 0.6, 0.8, 1.0). We show that the dominant exc…
Zener double exchange from local valence fluctuations in magnetite
R. J. McQueeney, M. Yethiraj, S. Chang +4
Magnetite (FeO) is a mixed valent system where electronic conductivity occurs on the B-site (octahedral) iron sublattice of the spinel structure. Below K, a…
The ground state of a quantum critical system
Wouter Montfrooij, Jagat Lamsal, Meigan Aronson +7
The competition between the tendency of magnetic moments to order at low temperatures, and the tendency of conduction electrons to shield these moments, can result in a phase trans…
Investigation of the presence of charge order in magnetite by measurement of the spin wave spectrum
R. J. McQueeney, M. Yethiraj, W. Montfrooij +3
Inelastic neutron scattering results on magnetite (Fe3O4) show a large splitting in the acoustic spin wave branch, producing a 7 meV gap midway to the Brillouin zone boundary at q…
Non-Fermi-liquid behavior in Ce(RuFe)Ge: cause and effect
W. Montfrooij, M. C. Aronson, B. D. Rainford +7
We present inelastic neutron scattering measurements on the intermetallic compounds Ce(RuFe)Ge (=0.65, 0.76 and 0.87). These compounds represent samples in a…
The Role of Grain Boundaries in Determining the Transport Properties in Magnetite
David C. Mertens, W. Montfrooij, R. J. McQueeney +2
We present magnetoresistance and Hall-effect measurements on single crystal magnetite Fe3O4 close to the Verwey transition Tv = 123.8 K. We show that the formation of grain boundar…
non-Local Quantum Criticality in Ce(Ru_{1-x} Fe_x)_2 Ge_2 (x = x_c = 0.76)
W. Montfrooij, M. C. Aronson, B. D. Rainford +4
We present the results of inelastic neutron scattering measurements, performed near the antiferromagnetic quantum critical point in Ce(Ru_{0.24} Fe_{0.76})_2 Ge_2. Both local and l…