Oblique spatial dark solitons in supersonic flow of Bose-Einstein condensate

In framework of the Gross-Pitaevskii mean field approach it is shown that supersonic flow of Bose- Einstein condensate can support a new type of pattern—an oblique spatial dark soliton. Exact spatial dark soliton solution of the Gross-Pitaevskii equation is obtained. It is demonstrated by numerical simulations that spatial solitons can be generated by an obstacle inserted into the flow. Connection of the developed theory with available experimental data is discussed.