物理学报
物理學報
물이학보
2013年
11期
271-275
,共5页
杨晓勇?%薛海斌%梁九卿
楊曉勇?%薛海斌%樑九卿
양효용?%설해빈%량구경
自旋相干态%变分法%J-C模型
自鏇相榦態%變分法%J-C模型
자선상간태%변분법%J-C모형
spin coherent-states%variational method%Jaynes-Cummings model
提出一种基于自旋相干态变换求解自旋-玻色模型基态的变分法,并将其用于单原子模型,得到旋波近似和非旋波近似情形下的解析基态能量和波函数,特别是在光场与原子的弱、强耦合区域都与数值对角化结果符合得很好.另外,该方法也可以直接用于求解任意原子数的Dicke模型基态和相应的量子相变研究,而通常基于Holstein-Primakoff变换的变分法,原则上只适用于原子数趋于无穷的热力学极限情形.
提齣一種基于自鏇相榦態變換求解自鏇-玻色模型基態的變分法,併將其用于單原子模型,得到鏇波近似和非鏇波近似情形下的解析基態能量和波函數,特彆是在光場與原子的弱、彊耦閤區域都與數值對角化結果符閤得很好.另外,該方法也可以直接用于求解任意原子數的Dicke模型基態和相應的量子相變研究,而通常基于Holstein-Primakoff變換的變分法,原則上隻適用于原子數趨于無窮的熱力學極限情形.
제출일충기우자선상간태변환구해자선-파색모형기태적변분법,병장기용우단원자모형,득도선파근사화비선파근사정형하적해석기태능량화파함수,특별시재광장여원자적약、강우합구역도여수치대각화결과부합득흔호.령외,해방법야가이직접용우구해임의원자수적Dicke모형기태화상응적양자상변연구,이통상기우Holstein-Primakoff변환적변분법,원칙상지괄용우원자수추우무궁적열역학겁한정형.
We present a variational method for the ground-state solutions of the spin-Bose models by means of the spin coherent-state transformation. For the Jaynes-Cummings (J-C) models with and without the rotating-wave approximation, the ground-state energies obtained by this method are in perfect agreement with the results from numerical diagonalization in the whole region of the coupling between a light field and an atom. The present variational-method can be directly used to solve the ground-state energies of the Dicke models with arbitrary atom-numbers and furoher study the quantum phase transition;while the variational-method based on the Holstein-Primakoff transformation is only valid in principle for the thermodynamic limit with the atom-number tending to infinity.
