نقدم في هذا المقال التقدم الحديث في فهم الحالات الأساسية والمثيرة للإشعاع الذي يرتبط بالإلكترون والفونون باستخدام طرق جديدة من الحساب الذهني الأحادي والتحسين الأحصائي، التي تتيح حساب الدالة الخضراء الماتسوباري في الأوقات الخيالية والاستمرار التحليلي بدون تشخيص إلى الترددات الحقيقية. نقدم نتائج عددية دقيقة حول خصائص الحالة الأساسية، ودالة اللايمان وموازنة الإشعاع البصري للنظم المرتبطة بشدة مختلفة: البولارون الفروليخ، والإكسيتون البولارون الراشبا-بيكار، والبولارون الجان-تلر الخاص، والإكسيتون، والثقب المتفاعل مع الفونون في النموذج t-J.
We present recent advances in understanding of the ground and excited states of the electron-phonon coupled systems obtained by novel methods of Diagrammatic Monte Carlo and Stochastic Optimization, which enable the approximation-free calculation of Matsubara Green function in imaginary times and perform unbiased analytic continuation to real frequencies. We present exact numeric results on the ground state properties, Lehmann spectral function and optical conductivity of different strongly correlated systems: Frohlich polaron, Rashba-Pekar exciton-polaron, pseudo Jahn-Teller polaron, exciton, and interacting with phonons hole in the t-J model.
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