雷德堡裝束之費米氣體的有序密度結構

Ordered Density Structure of Repulsive Rydberg-dressed Fermionic Atoms

李威漢(Li, Wei Han)

指導教授 ： 王道維

國立清華大學/理學院/物理學系/碩士(2015年)

https://doi.org/10.6843/NTHU.2015.00233

摘要

此文章研究雷德保裝束(Rydberg-dressed)費米氣體在三維自由空間中的量子相轉變現象。由隨機相位近(random phase approximation)計算得知，若原子的雷德堡阻絕長度(Rydberg blockade length)夠長，或者系統密度夠高，微弱的交互作用即可使均勻的費米液體系統中出現有序密度波。我們的平均場理論(mean-field theory)結果顯示，系統經由一級相轉變過程形成具有體心立方晶格結構的有序密度波，並且其相轉變溫度約為費米能階的十分之一。再者，此研究涉及的理論徹底不同於已知的藍道費米液體理論，意即此有序密度結構非藍道費米液體理論所能預期。

關鍵字

雷德堡裝束 ； 費米子 ； 量子相轉變 ； 有序密度波

並列摘要

We study quantum phase transitions of a repulsive Rydberg-dressed Fermi gas
in 3D free space. Under random phase approximation(RPA), it is shown that a
density wave order emerges from a Fermi liquid within week interaction and long
blockade length (or high density) regime. Our mean-field theory results show that,
this density wave order forms BCC structure through a first order phase transition,
and the transition temperature is about one-tenth of the Fermi energy. Further-
more, we argue that the theory associated with this novel phenomenon of repulsive
Fermionic system differs completely from the well known Landau Fermi liquid
theory.

並列關鍵字

Rydberg-dressed ； Fermion ； Quantum phase transition ； density wave order

參考文獻

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