武汉物理与数学研究所：To resolve the mystery of superfluidity and supersolidity（PPT讲稿）superfluidity as a Bose exchange effect

h2、0 H ∑n+27g∑8( 2MR480 Exact diagonalization n(0)=em,m=0,±1,+2,+3, many body Fock state mnm2“mn3…), n, particles in m, n, particles in m, n, particles in p, n1+n2+n3+…=N nm1 +nm、+m2+.=L

Exact diagonalization: ( ) , 0, 1, 2, 3,... im m e m   = =    2 2 2 2 1 2 ( ) 2 N N i j i i j i H g MR     =    = − + −    1 2 3 1 2 3 1 2 3 1 2 3 many body Fock state: particles in particles in particles in | ... , , , ,... n n n m m m m m m n n n     1 2 3 1 1 2 2 3 3 ... ... n n n N n m n m n m L + + + = + + + =

h2、0 H ∑n+27g∑8( 2MR480 Exact diagonalization n(0)=em,m=0,±1,+2,+3, many body Fock state mnm2“mn3…), n, particles in m, n, particles in m, n, particles in p, n1+n2+n3+…=N 1m1+2m2+nym3+…=L Em:n1m2+n2m2+13m32+

Exact diagonalization: ( ) , 0, 1, 2, 3,... im m e m   = =    2 2 2 2 1 2 ( ) 2 N N i j i i j i H g MR     =    = − + −    1 2 3 1 2 3 1 2 3 1 2 3 many body Fock state: particles in particles in particles in | ... , , , ,... n n n m m m m m m n n n     1 2 3 1 1 2 2 3 3 ... ... n n n N n m n m n m L + + + = + + + = 2 2 2 1 1 2 2 3 3 ... : E n m n m n m kin + + +

gs)=cn|0~)+c|(-1)0~21)+c2|(-1)0~32)+ L=1)=dn|0-1)+d|(-1)02)+d2|(-1)0~-31)+

1 1 2 1 0 1 2 1 1 1 1 2 0 1 2 2 3 1 2 3 1 2 1 2 1 | . . |0 |( 1) 0 |( 1) 0 ... | 1 |0 |( 1) 0 |( 1) 0 ... N N N N N N g s c c c L d d d − − − − −  =  + −  + −  + =  =  + −  + −  +

Method one Perturbation analysis 10 L

Method one: Perturbation analysis

10 L