我們研究了SU(N)對稱破壞的量子淬火在SU(N)費米氣體中所導致的預熱(pre-thermalization)以及自旋翻轉轉碰撞。我們分析了對於不同的起始自旋極化狀態的影響並發現對自旋翻轉會壓抑預熱的產生。我們還研究了淬火時間的影響，對於較長的淬火時間系統會傾向於其平衡態的行為。

We explore the short-time evolution of an SU(N) Fermi-liquid following the quench of a SU(N)-symmetry interaction.
The conditions for the existence of a pre-thermalized regime
after turning on the interaction strength are analyzed.
We find that spin-changing collisions play an important role in suppressing pre-thermalization for spin-polarized initial states. For an unpolarized (i.e. SU$(N)$ symmetric) initial ground state, a pre-thermalized regime is observed, which is
robust to presence of (SU$(N)$-symmetric) interactions in the initial state. We also study the short-time dynamics
for finite-time ramps of the interaction strength.
For long ramp-time, the value of the discontinuity approaches the equilibrium value of the post-quench Hamiltonian.

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