Magnon excitations and quantum critical behavior of the ferromagnet U4Ru7Ge6

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F18%3A10385390" target="_blank" >RIV/00216208:11320/18:10385390 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.1103/PhysRevB.98.174431" target="_blank" >https://doi.org/10.1103/PhysRevB.98.174431</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/PhysRevB.98.174431" target="_blank" >10.1103/PhysRevB.98.174431</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Magnon excitations and quantum critical behavior of the ferromagnet U4Ru7Ge6

Popis výsledku v původním jazyce

We present an extensive study of the ferromagnetic heavy-fermion compound U4Ru7Ge6. Measurements of electrical resistivity, specific heat, and magnetic properties show that U4Ru7Ge6 orders ferromagnetically at ambient pressure with a Curie temperature T-C = 6.8 +/- 0.3 K. The low-temperature magnetic behavior of this soft ferromagnet is dominated by the excitation of gapless spin-wave modes. Our results on the transport properties of U(4)Ru(7)Ge(6 )under pressures up to 2.49 GPa suggest that U4Ru7Ge6 has a putative ferromagnetic quantum critical point (QCP) at P-c approximate to 1.7 +/- 0.02 GPa. In the ordered phase, ferromagnetic magnons scatter the conduction electrons and give rise to a well-defined power law temperature dependence in the resistivity. The coefficient of this term is related to the spin-wave stiffness, and measurements of the very low temperature resistivity show the behavior of this quantity as the ferromagnetic QCP is approached. We find that the spin-wave stiffness decreases with increasing pressure, implying that the transition to the nonmagnetic Fermi liquid state is driven by the softening of the magnons. The observed quantum critical behavior of the magnetic stiffness is consistent with the influence of disorder in our system. At quantum criticality (P = P-c approximate to 1.7 +/- 0.02 GPa), the resistivity shows the behavior expected for an itinerant metallic system near a ferromagnetic QCP.

Název v anglickém jazyce

Magnon excitations and quantum critical behavior of the ferromagnet U4Ru7Ge6

Popis výsledku anglicky

We present an extensive study of the ferromagnetic heavy-fermion compound U4Ru7Ge6. Measurements of electrical resistivity, specific heat, and magnetic properties show that U4Ru7Ge6 orders ferromagnetically at ambient pressure with a Curie temperature T-C = 6.8 +/- 0.3 K. The low-temperature magnetic behavior of this soft ferromagnet is dominated by the excitation of gapless spin-wave modes. Our results on the transport properties of U(4)Ru(7)Ge(6 )under pressures up to 2.49 GPa suggest that U4Ru7Ge6 has a putative ferromagnetic quantum critical point (QCP) at P-c approximate to 1.7 +/- 0.02 GPa. In the ordered phase, ferromagnetic magnons scatter the conduction electrons and give rise to a well-defined power law temperature dependence in the resistivity. The coefficient of this term is related to the spin-wave stiffness, and measurements of the very low temperature resistivity show the behavior of this quantity as the ferromagnetic QCP is approached. We find that the spin-wave stiffness decreases with increasing pressure, implying that the transition to the nonmagnetic Fermi liquid state is driven by the softening of the magnons. The observed quantum critical behavior of the magnetic stiffness is consistent with the influence of disorder in our system. At quantum criticality (P = P-c approximate to 1.7 +/- 0.02 GPa), the resistivity shows the behavior expected for an itinerant metallic system near a ferromagnetic QCP.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10302 - Condensed matter physics (including formerly solid state physics, supercond.)

Projekt

<a href="/cs/project/LM2011025" target="_blank" >LM2011025: LMNT - Laboratoře magnetizmu a nízkých teplot - provoz a rozvoj národní výzkumné infrastruktury</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2018

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Physical Review B

ISSN

2469-9950

e-ISSN

—

Svazek periodika

98

Číslo periodika v rámci svazku

17

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

10

Strana od-do

—

Kód UT WoS článku

000451330200005

EID výsledku v databázi Scopus

2-s2.0-85057357205