Enhancing the geometric quantum discord in the Heisenberg {\it XX} chain   by Dzyaloshinsky-Moriya interaction
  We studied the trance distance, the Hellinger distance, and the Bures distance geometric quantum discords (GQDs) for a two-spin Heisenberg {\it XX} chain with the Dzyaloshinsky-Moriya (DM) interaction and the external magnetic fields. We found that considerable enhancement of the GQDs can be achieved by introducing the DM interaction, and their maxima were obtained in the limiting case $D\rightarrow \infty$. The external magnetic fields and the increase of the temperature can also enhance the GQDs to some extent for certain special cases. 
Jia-Min Gong, Qi Tang, Yu-Hang Sun, Lin Qiao
quant-ph