For suitable values of the differences between chemical potentials,Cooper pairs with non-zero total momentum are favored,as was first realized by Larkin,Ovchinnikov,Fulde and Ferrell(LOFF).

• 当化学势的差别达到某一合适值时,库柏对就有非零的总动量,这就是Larkin-Ovchinnikov-Fulde-Ferre(LOFF)态。