SciPost Commentary Page
Original publication:
| Title: | Chirality and orbital order in charge density waves |
| Author(s): | Jasper van Wezel |
| As Contributors: | Jasper van Wezel |
| Journal ref.: | EPL (Europhysics Letters) 96, 67011 |
| DOI: | http://dx.doi.org/10.1209/0295-5075/96/67011 |
| Date: | 2011-12-01 |
Abstract:
Helical arrangements of spins are common among magnetic materials. The first material to harbor a corkscrew pattern of charge density, on the other hand, was discovered only very recently. The nature of the order parameter is of key relevance, since rotating a magnetic vector around any propagation vector trivially yields a helical pattern. In contrast, the purely scalar charge density cannot straightforwardly support a chiral state. Here we use a Landau order parameter analysis to resolve this paradox, and show that the chiral charge order may be understood as a form of orbital ordering. We discuss the microscopic mechanism driving the transition and show it to be of a general form, thus allowing for a broad class of materials to display this novel type of orbital-ordered chiral charge density wave.
Jasper van Wezel on 2019-04-11 [id 495]
Please note that the atomic structure of the chiral phase in $1T$-TiSe$_2$ actually has the (base-centred) space group C2, rather than the (primitive) space group P2 mentioned in the paper.
I would like to thank Suyang Xu for pointing this out.