Screening of a Point Charge : A Fixed - Node
نویسندگان
چکیده
We study the static screening in a Hubbard-like model using xed-node diiusion Monte Carlo. We nd that the random phase approximation is surprisingly accurate even for metallic systems close to the Mott transition. As a speciic application we discuss the implications of the eecient screening for the supercon-ductivity in the doped Fullerenes. In the Monte Carlo calculations we use trial functions with two Gutzwiller-type parameters. To deal with such trial functions, we introduce a method for eeciently optimizing the Gutzwiller parameters, both in variational and in xed-node diiusion Monte Carlo.
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تاریخ انتشار 2007