مكثف بوز-أينشتاين

(تم التحويل من مكثف بوز–أينشتاين)

مكثـَّـف بوز-أينشتاين Bose-Einstein Condensate هي مادة تتصرف بطريقة غير طبيعية فقط عند درجات حرارة شديدة الإنخفاض، ربما عند كسر من البليون من درجة فوق الصفر المطلق. وعند تلك النقطة تصبح قوانين الثرموديناميكا هامة جداً.

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النظرية

حيث:

 is  the critical temperature,
 is  the particle density,
 is  the mass per boson,
 is  Planck's constant,
 is  the Boltzmann constant, and
 is  the Riemann zeta function; (sequence A078434 in OEIS)


دفوعات أينشتاين

للقيم الكبيرة من N ، فإن ثابت الـnormalization ‏ C هو (1-p). العدد الإجمالي المتوقع للجسيمات اللائي لسن في حالة أقل طاقة، في النهاية التي , is equal to . It doesn't grow when N is large, it just approaches a constant. This will be a negligible fraction of the total number of particles. So a collection of enough bose particles in thermal equilibrium will mostly be in the ground state, with only a few in any excited state, no matter how small the energy difference.

مخطط بيانات توزيع السرعة

Velocity-distribution data of a gas of rubidium atoms, confirming the discovery of a new phase of matter, the Bose–Einstein condensate. Left: just before the appearance of the Bose–Einstein condensate. Center: just after the appearance of the condensate. Right: after further evaporation, leaving a sample of nearly pure condensate.

الدوامات

الخصائص عير المعتادة

طالع أيضاً

المصادر

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الهامش

وصلات خارجية