EPL, 77 (2007) 56004
DOI: 10.1209/0295-5075/77/56004

Observation of phasons in the magnetic shape memory alloy

S. M. Shapiro¹, P. Vorderwisch², K. Habicht², K. Hradil³ and H. Schneider<sup>3

1</sup>  Brookhaven National Laboratory - PO Box 5000, Upton, NY
²  Hahn-Meitner Institut - Berlin, Germany
³  Georg-August-Universität - Göttingen, Germany

received 9 November 2006; accepted in final form 17 January 2007; published March 2007
published online 26 February 2007

Abstract
An inelastic neutron scattering study of the lattice dynamics of the martensite phase of the ferromagnetic shape memory alloy, Ni₂MnGa, reveals the presence of well-defined phasons associated with the charge density wave (CDW) resulting from Fermi surface (FS) nesting. The velocity and the temperature dependence of the phason are measured as well as the anomalous [110]-TA₂ phonon.

PACS
61.12.-q - Neutron diffraction and scattering.
71.45.Lr - Charge-density-wave systems.
81.30.Kf - Martensitic transformations.

© Europhysics Letters Association 2007