Macroscopic properties of triplon Bose–Einstein condensates

Macroscopic Quantum Coherence in Bose–Einstein Condensates

The density of a Bose Einstein condensate (BEC) can undergo a symmetry breaking, either in real space or in momentum space. This occurs in a double well potential, obtained in real space for a BEC of lithium atoms by adding a standing wave light field to the trap potential, or in momentum space for rubidium atoms by Raman coupling two BECs in different magnetic states with two tilted light fiel...

Pulsed Macroscopic Quantum Tunneling of Falling Bose Condensates

We investigate macroscopic quantum tunneling of a Bose condensate and how it is affected by the interatomic interaction. We study the dynamics of a condensate falling under gravity and scattering on a Gaussian potential barrier that models a mirror formed by a far-detuned sheet of light. We observe bouncing, interference and quantum tunneling of the condensate. We find that the tunneling rate i...

Macroscopic quantum coherence phenomena in Bose Einstein Condensates

control of the optical properties of nanoparticles by laser fields

در این پایان نامه، درهمتنیدگی بین یک سیستم نقطه کوانتومی دوگانه(مولکول نقطه کوانتومی) و میدان مورد مطالعه قرار گرفته است. از آنتروپی ون نیومن به عنوان ابزاری برای بررسی درهمتنیدگی بین اتم و میدان استفاده شده و تاثیر پارامترهای مختلف، نظیر تونل زنی(که توسط تغییر ولتاژ ایجاد می شود)، شدت میدان و نسبت دو گسیل خودبخودی بر رفتار درجه درهمتنیدگی سیستم بررسی شده اشت.با تغییر هر یک از این پارامترها، در...

Dynamic Properties of Dilute Bose-Einstein Condensates

In this thesis, a new apparatus for the study of Bose-Einstein condensation is described, and the first two experiments performed with the new device are discussed. The new instrument was constructed for the creation of dilute gas sodium Bose-Einstein condensates, and features an optical quality quartz cell, a high-flux spin-flip Zeeman slower, a tightly confining magnetic trap, and a high-reso...