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تسجيل مستخدم جديدعلاقات التقلبات الحرارية الكمونية في الأنظمة المستوى $3$ تحت القياسات المشروعية
Quantum-heat fluctuation relations in $3$-level systems under projective measurements
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تدرسنا إحصاءات الانزلاقات الطاقية في نظام كمي ثلاثي المستويات الذي يتحمل سلسلة من القياسات الكمية المشروعة. نحن نتحقق من أن المساواة الجارزينسكي الكمية تحقق كما هو متوقع إذا تم تلبية الشرط الأولي الحراري. هذا الشرط يتلبى بسهولة للنظم المستويين، بينما هو عادة غير صحيح للنظم $N$ المستوية، مع $N > 2$. متركزين على النظم الثلاثية المستوية، نناقش وجود عامل مقياس طاقة فريد $beta_{rm eff}$ الذي يلعب دوراً رسمياً لدرجة حرارة معكوسة في المساواة الجارزينسكي الكمية. لهذا الغرض، ندخل تهيئة مناسبة للحالة الأولية بالنسبة إلى جزء حراري وجزء غير حراري. نحدد قيمة $beta_{rm eff}$ لعدد كبير من القياسات وندرس تبعيتها على الحالة الأولية. يمكن التحقق من توقعاتنا على الأحداثيات الكمية.
We study the statistics of energy fluctuations in a three-level quantum system subject to a sequence of projective quantum measurements. We check that, as expected, the quantum Jarzynski equality holds provided that the initial state is thermal. The latter condition is trivially satisfied for two-level systems, while this is generally no longer true for $N$-level systems, with $N > 2$. Focusing on three-level systems, we discuss the occurrence of a unique energy scale factor $beta_{rm eff}$ that formally plays the role of an effective inverse temperature in the Jarzynski equality. To this aim, we introduce a suitable parametrization of the initial state in terms of a thermal and a non-thermal component. We determine the value of $beta_{rm eff}$ for a large number of measurements and study its dependence on the initial state. Our predictions could be checked experimentally in quantum optics.
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