RT Journal T1 Gradient Flow Method in Nonlinear Optical Lattices A1 Ruifeng Zhang,Nan Liu PB Acta mathematica scientia,Series A FD 2019-10-26 YR 2019 JF Acta mathematica scientia, Series A JO Acta mathematica scientia,Series A VO 39 IS 5 SP 1170 DO K1 ;Gradient flow method;Schrödinger Equation;Łojasiewicz-Simon inequality;Steady state solutions LK {http://121.43.60.238/sxwlxbA/EN/article/article_15961.shtml}