اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدتطبيق تأثيرات الارتباط باستخدام التفاعلات الإلكترون-فونون
Tuning correlation effects with electron-phonon interactions
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نحن نقوم بتحقيق تأثير تحكم في طاقة الفونون على التأثيرات الارتباطية في نماذج التفاعلات الإلكترون-فونون باستخدام DMFT. في النطاق الذي يتنافس فيه الإلكترونات المسافرون والتأثيرات المدفوعة عن طريق الإلكترون-فونون الفورية والتشوهات الثابتة على مستويات طاقة متشابهة، نجد عدداً من النتائج المثيرة للاهتمام من بينها (1) تحول من الحزمة إلى السلوك الموت في الوظيفة الطيفية، مما يؤدي إلى تشكيل ميزات مختلطة بين الحزمة والموت في الوظيفة الطيفية للفونون بمعدلات أكثر من العرض الحزمة. (2) وبما أن السماحية البصرية تعتمد بشكل حساس على شكل الوظيفة الطيفية، نظرنا إلى أن هذا النطاق ينبغي أن يكون ملحوظاً من خلال شكل السماحية البصرية على مستوى الأداء المنخفض. (3) وتحتوي المقاومة على تركيبة من ذراعي الكوندو المزدوجة.
We investigate the effect of tuning the phonon energy on the correlation effects in models of electron-phonon interactions using DMFT. In the regime where itinerant electrons, instantaneous electron-phonon driven correlations and static distortions compete on similar energy scales, we find several interesting results including (1) A crossover from band to Mott behavior in the spectral function, leading to hybrid band/Mott features in the spectral function for phonon frequencies slightly larger than the band width. (2) Since the optical conductivity depends sensitively on the form of the spectral function, we show that such a regime should be observable through the low frequency form of the optical conductivity. (3) The resistivity has a double kondo peak arrangement
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