We develop a FORTRAN code to compute fluctuations in atomic condensates (FACt) by solving the Bogoliubov-de Gennes (BdG) equations for two component Bose-Einstein condensate (TBEC) in quasi two dimensions. The BdG equations are recast as matrix equations and solved self consistently. The code is suitable for handling quantum fluctuations as well as thermal fluctuations at temperatures below the critical point of Bose-Einstein condensation. The code is versatile, and the ground state density profile and low energy excitation modes obtained from the code can be easily adapted to compute different properties of TBECs --- ground state energy, overlap integral, quasi particle amplitudes of BdG spectrum, dispersion relation and structure factor and other related experimental observables.

中文翻译：

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事实：用于计算原子凝聚态波动的 FORTRAN 工具箱

我们开发了一个 FORTRAN 代码，通过求解准二维中两分量玻色-爱因斯坦凝聚 (TBEC) 的 Bogoliubov-de Gennes (BdG) 方程来计算原子凝聚 (FACt) 的波动。BdG 方程被改写为矩阵方程并自求解。该代码适用于处理量子涨落以及低于玻色-爱因斯坦凝聚临界点的温度下的热涨落。该代码具有通用性，从代码中获得的基态密度剖面和低能量激发模式可以很容易地适应计算 TBEC 的不同性质——基态能量、重叠积分、BdG 谱的准粒子幅度、色散关系和结构因子和其他相关的实验观测值。