TY - GEN A1 - Seibold, Götz A1 - Bucheli, Daniel A1 - Caprara, Sergio A1 - Grilli, Marco T1 - Phase separation and long-wavelength charge instabilities in spin-orbit coupled systems T2 - EPL Europhysics Letters N2 - We investigate a two-dimensional electron model with Rashba spin-orbit interaction where the coupling constant $g=g(n)$ depends on the electronic density. It is shown that this dependence may drive the system unstable towards a long-wavelength charge density wave (CDW) where the associated second-order instability occurs in close vicinity to global phase separation. For very low electron densities the CDW instability is nesting-induced and the modulation follows the Fermi momentum kF. At higher density the instability criterion becomes independent of kF and the system may become unstable in a broad momentum range. Finally, upon filling the upper spin-orbit split band, finite momentum instabilities disappear in favor of phase separation alone. We discuss our results with regard to the inhomogeneous phases observed at the LaAlO3/SrTiO3 or LaTiO3/SrTiO3 interfaces. Y1 - 2016 UR - https://opus4.kobv.de/opus4-UBICO/frontdoor/index/index/docId/17577 UR - http://iopscience.iop.org/article/10.1209/0295-5075/109/17006;jsessionid=34AAE2057398BD7AE51C0C4719FC29DD.c2.iopscience.cld.iop.org SN - 1286-4854 VL - 109 IS - 1 SP - 17006 ER -