Quantum order-by-disorder near criticality and the secret of partial order in MnSi
View/ Open
Date
08/02/2012Grant ID
EP/H049584/1
EP/I031014/1
EP/I004831/1
Metadata
Show full item recordAbstract
The vicinity of quantum phase transitions has proven fertile ground in the search for new quantum phases. We propose a physically motivated and unifying description of phase reconstruction near metallic quantum-critical points using the idea of quantum order-by-disorder. Certain deformations of the Fermi surface associated with the onset of competing order enhance the phase space available for low-energy, particle-hole fluctuations and self-consistently lower the free energy. Applying the notion of quantum order-by-disorder to the itinerant helimagnet MnSi, we show that near to the quantum critical point, fluctuations lead to an increase of the spiral ordering wave vector and a reorientation away from the lattice favored directions. The magnetic ordering pattern in this fluctuation-driven phase is found to be in excellent agreement with the neutron scattering data in the partially ordered phase of MnSi.
Citation
Kruger , F , Karahasanovic , U & Green , A G 2012 , ' Quantum order-by-disorder near criticality and the secret of partial order in MnSi ' , Physical Review Letters , vol. 108 , no. 6 , 067003 . https://doi.org/10.1103/PhysRevLett.108.067003
Publication
Physical Review Letters
Status
Peer reviewed
ISSN
0031-9007Type
Journal article
Rights
© 2012 American Physical Society
Collections
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.