Published in:

Physical Review B 75,1 (2007) 012414;


Recent neutron scattering measurements reveal spin and charge ordering in the half-doped nickelate, La3/2Sr1/2NiO4. Many of the features of the magnetic excitations have been explained in terms of the spin waves of diagonal stripes with a magnetic coupling structure which is fourfold symmetric. However, an optical mode dispersing away from the (pi,pi) point was not captured by this theory. We show here that this apparent optical mode is a natural consequence of stripe twinning in a diagonal stripe pattern with a magnetic coupling structure which is twofold symmetric, i.e., one possessing the same spatial rotational symmetry as the ground state.


Physics, Condensed Matter

Date of this Version

January 2007



To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.