Extremely correlated quantum liquids

Physical Review B - Condensed Matter and Materials Physics

Volumn 81, Issue 4, 2010, Pages

  Shastry, B Sriram ^a  

^a UNIVERSITY OF CALIFORNIA   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 77954820833     PISSN: 10980121     EISSN: 1550235X     Source Type: Journal    
DOI: 10.1103/PhysRevB.81.045121     Document Type: Article

References (74)

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68. At the time of completing the mansuscript, we noticed papers on the t - J model, Ref., with some initial overlap with our method. We differ in much of the details and the conclusions. These authors consider only density (but not spin)-dependent sources, and thus do not obtain the analogs of most of our main results, e.g., the exact Schwinger Dyson equation, Eq.. They further make what seem to be uncontrolled approximations, leading to results that are in disagreement with ours. For instance, they find an effective band that vanishes as (1 - n) near half filling, in contrast to our reduction in the bandwidth by spin and density correlations.
69. Prof. P. Phillips has brought to my attention a recent preprint: S. Chakraborty, S. Hong, and P. Phillips, arXiv:0909.3069 (unpublished), where charge 2 e objects arise dynamically in the Hubbard model.
70. Its functional derivatives w.r.t. the sources also seems negligible at first sight but we plan to check this more carefully later. For now it must be taken as an assumption for the vertex that is certainly consistent with the Ward identity.
71. This analysis parallels that of Sec. 6.1 for the Bethe Salpeter equations for particle-hole multiple scattering (Ref.).
72. There is another way to group particles and holes leading to a second particle-hole channel familiar in parquet theory but we will choose this present one since it is most relevant.
73. The vertices obtained from this atomic Green's function and the "untreated" self-energy where the transformation, Eq., has not been done, are easily seen to contain linear terms at high frequency and hence are examples of a "sick" theory.
74. We have preliminary results showing how the singular part of the self-energy and the Luttinger-Ward functional arise from a partial summation of an infinite set of diagrams in perturbation theory of the Hubbard model.