Multicomponent fluctuation spectrum at the quantum critical point in CeCu6−xAgx

Abstract

Quantum critical points (QCPs) are widely accepted as a source of a diverse set of collective quantum phases of matter. The basic nature of a QCP is manifested in the critical fluctuation spectrum which in turn is determined by the adjacent phases and associated order parameters. Here we show that the critical fluctuation spectrum of CeCu 5.8 Ag 0.2 can not be explained by fluctuations associated with a single wave vector. Interestingly, when the critical fluctuations at wave vectors corresponding to the incommensurate antiferromagnetic order adjacent to the QCP are separated they are found to be three dimensional and to obey the scaling behavior expected for long wavelength fluctuations near an itinerant antiferromagnetic QCP. Without this separation, E/ T scaling with a fractional exponent is observed. Together these results demonstrate that a multicomponent fluctuation spectrum is a previously unexplored route to obtaining E/T scaling at a QCP.

Role of local Ru hexamers in superconductivity of ruthenium phosphide

“…Spatiotemporal fluctuations of electronic charge, orbital, and spin are native to the quantum materials realm [1][2][3][4][5], encompassing phenomena ranging from unconventional superconductivity [6,7], charge density waves [8,9], and pseudogaps [10] to metal-insulator transitions [11,12], colossal magnetoresistivity [13], and frustrated magnetism [14,15]. Elucidating the character and role of electronic short-range correlations in the emergence of application-relevant phases [16][17][18][19][20][21][22][23][24][25] is challenging as most experimental probes yield bulk averages [26][27][28]. When the crystal lattice is involved, the pair distribution function (PDF) approach provides a unique perspective informing on the presence and nature of states of local broken symmetry on the nanoscale [29].…”

Fluctuating Ru trimer precursor to a two-stage electronic transition in RuP

“…Spatiotemporal fluctuations of electronic charge, orbital, and spin are native to the quantum materials realm [1][2][3][4][5], encompassing phenomena ranging from unconventional superconductivity (SC) [6,7], charge density waves [8,9], and pseudogaps (PGs) [10] to metal-insulator transitions [11,12], colossal magnetoresistivity [13], and frustrated magnetism [14,15]. Elucidating the character and role of electronic shortrange correlations in the emergence of application-relevant phases [16][17][18][19][20][21][22][23][24][25] is challenging as most experimental probes yield bulk averages [26][27][28]. When the crystal lattice is involved, the pair distribution function (PDF) approach provides a unique perspective informing on the presence and nature of states of local broken symmetry on the nanoscale [29].…”