我們提出一種全新的混合顆粒分離機制，在這個機制中不同種類顆粒間的交互作用是動態地被顆粒的相位同步現象所引發。藉由這樣的想法，我們利用分子動力模擬顯示混合顆粒的分離可以發生在當兩種顆粒僅僅只有恢復係數的差別時。這個新的分離現象不能被目前任何已知的分離機制所解釋，例如著名的巴西豆效應只存在於顆粒大小或質量有差異時、Depletion Force則只適用在顆粒大小有差異的時候。我們提出的相位同步機制可以良好的解釋這種新的分離現象，配合線性穩定性分析(linear stability analysis)而非常精準的計算出分離的條件與分離相圖的形狀。在重力可忽略的條件下，我們得到了分離條件的解析解。我們的理論推導與分子動力模擬的結果非常吻合。由於我們模擬的顆粒系統發生分離時的行為相當類似於熱力學系統的二相分離現象，因此我們也討論了兩著的差異，包含特徵長度隨時間的演變速度與order parameter相關的動能分布等等性質。其中較為特別的現象是兩種混合顆粒在發生分離的過程中會具有不同的動能大小，這是一般熱力學系統所沒有的特徵。同時我們也分析了特徵長度演化的尺度率，發現特徵長度與時間的關係符合power law的分布。雖然這與熱力學系統的相分離現象相同，但我們系統所展現的power law指數卻是低於已知的熱力學系統分離的指數。

We propose a novel segregation mechanism where the species-dependent interactions are dynamically induced by the phase synchronization of beads. Based on this scenario, we report a new segregation among beads of different restitution coefficients by the molecular dynamics simulations. Since the beads are of equal size and mass, this is not related to the Brazilian-nut effect, nor can it be explained by the depletion force, or other related segregation mechanisms proposed so far. Instead, this phenomenon derives from the phase synchronization, which concept helps us determine the criteria for segregation and the phase boundaries that agree excellently with the simulation results.

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