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تسجيل مستخدم جديدشخصيات بوسونية لأزواج كوبر الذرية عبر الإشتراك
Bosonic characters of atomic Cooper pairs across resonance
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إننا ندرس دالة الموجة للجسيمين المزدوجين للأشعاعات الفرمي في حالة التفاعل القابل للتحكم بواسطة الإشعاع الفيشباخ. ونقوم بفحص دالة الموجة للزوج الكوبر لصفاته البوزونية، والتي تقيس بواسطة تصحيح العامل الزيادة البوزي المرتبط بمؤثرات خلق وإنقاص الجسيم المركب. ويوضح ذلك بمثال لغاز متساوي الأبعاد. ونقوم بفحص اثنين من تعريفات دالة الموجة للزوج الكوبر. واحد منهم يختار للتعكير على النظام الطويل المنحني الغير العامودي (ODLRO). والآخر يتطابق مع عملية التشخيص لدولة BCS. وعلى الجانب الذي يتميز بطول الانحدار السالب، وجدنا أن الأشعاعات المزدوجة التي توصف بـ ODLRO أكثر بوزونية من تعريف التشخيص. وأيضاً أظهر البحث أنه عند $(k_F a)^{-1} ge 1$، فإن كلا التعريفين يعطيان نتائج متشابهة، حيث أن أكثر من 90٪ من الأشعاعات يشغلان التراكيز المولية المطابقة.
We study the two-particle wave function of paired atoms in a Fermi gas with tunable interaction strengths controlled by Feshbach resonance. The Cooper pair wave function is examined for its bosonic characters, which is quantified by the correction of Bose enhancement factor associated with the creation and annihilation composite particle operators. An example is given for a three-dimensional uniform gas. Two definitions of Cooper pair wave function are examined. One of which is chosen to reflect the off-diagonal long range order (ODLRO). Another one corresponds to a pair projection of a BCS state. On the side with negative scattering length, we found that paired atoms described by ODLRO are more bosonic than the pair projected definition. It is also found that at $(k_F a)^{-1} ge 1$, both definitions give similar results, where more than 90% of the atoms occupy the corresponding molecular condensates.
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