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Dramatic effective mass reduction driven by strong electronic correlations

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 نشر من قبل Claude Monney
 تاريخ النشر 2009
  مجال البحث فيزياء
والبحث باللغة English
 تأليف C. Monney




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We present angle-resolved photoemission experiments on 1T-TiSe2 at temperatures ranging from 13K to 288K. The data evidence a dramatic renormalization of the conduction band below 100K, whose origin can be explained with the exciton condensate phase model. The renormalization translates into a substantial effective mass reduction of the dominant charge carriers and can be directly related to the low temperature downturn of the resistivity of 1T-TiSe2. This observation is in opposition to the common belief that strong interactions produce heavier quasiparticles through an increased effective mass.

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