اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدالتحولات من الدوران العالي إلى الدوران المنخفض والتشديد الأوربيتي في النظم الموت المتعددة المناطق
High-spin to low-spin and orbital polarization transitions in multiorbital Mott systems
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نحن ندرس تداخل التفرع المجال البلوري وربط هند في نموذج مؤثر بطريقتين المضمنة الفيزياء الأساسية للأنظمة مع إثنين من الإشعاعات أو الثقوب في غشاء e_g. نحن نستخدم الحقل المتحرك الموحد الموجز مع محلل عقار حديث الذي يمكنه الوصول إلى ربطات قوية ودرجات حرارة منخفضة. يتم حساب ملء المراكز الأوربيتالية ومواقع حدود المرحلة كدالة من الانزعاج الكولومبي والربط التبادل والتفرع المجال البلوري. نجد أن الربط هند يمكن أن يدفع النظام إلى مجال مغناطيسي موت جديد مع تحسس الأوربيتال الصفر. بعيدا عن الملء النصفي، يمكن للتفرع المجال البلوري أن يؤدي إلى حالة موت أوربيتالية محددة.
We study the interplay of crystal field splitting and Hund coupling in a two-orbital model which captures the essential physics of systems with two electrons or holes in the e_g shell. We use single site dynamical mean field theory with a recently developed impurity solver which is able to access strong couplings and low temperatures. The fillings of the orbitals and the location of phase boundaries are computed as a function of Coulomb repulsion, exchange coupling and crystal field splitting. We find that the Hund coupling can drive the system into a novel Mott insulating phase with vanishing orbital susceptibility. Away from half-filling, the crystal field splitting can induce an orbital selective Mott state.
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