Extended coupled-cluster method. II. Excited states and generalized random-phase approximation
نویسندگان
چکیده
منابع مشابه
Quantum phase transitions and the extended coupled cluster method.
We discuss the application of an extended version of the coupled cluster method to systems exhibiting a quantum phase transition. We use the lattice O(4) nonlinear sigma model in (1+1) and (3+1) dimensions as an example. We show how simple predictions get modified, leading to the absence of a phase transition in (1+1) dimensions, and strong indications for a phase transition in (3+1) dimensions.
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ژورنال
عنوان ژورنال: Physical Review A
سال: 1987
ISSN: 0556-2791
DOI: 10.1103/physreva.36.2539