當受驅動的固體因外部應力屈服時，會經歷間歇性黏滯滑移（stick-slip）的「微震」，將累積的彈性應變能以聲發射（acoustic emission， AE）波形式迅速釋放。從巨觀地質斷層到局域金屬玻璃剪切帶，這種塑性失效皆受到微觀結構重整（structural rearrangements， SRs）與聲波（acoustic waves， AWs）傳播間複雜交互作用的控制。然而，傳統原子分子系統受限於極端的微觀時空尺度，科學家完全無法觀測單個粒子的動態演變；膠體或顆粒等軟物質系統雖具備單粒子解析能力，且在結構軟點預測或剪切帶雪崩與波動傳遞上已有許多發現，但過去研究極少關注兩者在真實空間中的時空演變與直接因果關係。因此，如何在最根本的微觀尺度下，將單一離散的四粒子鍵交換（T1轉換）事件，與橫向、縱向發射波場的同時激發、能量分配及時空輻射建立因果鏈結，至今仍是一個未被探索的領域。 為了跨越這一關鍵的因果關係鴻溝，本研究以定常雷射剪切驅動的強耦合二維（2D）塵埃電漿（dusty plasma）晶體單層作為類比實驗平台。得益於懸浮塵埃粒子的宏觀尺度與變慢的動力學，我們得以直接光學追蹤個別粒子的微觀運動軌跡，並將經驗模態分解法（EMD）自適應地應用於真實空間的粒子位移中，將非穩態的聲學漲落從主導的背景剪切流中分離。 實驗結果表明，剪切晶體內的塑性屈服展現出顯著的黏滯滑移間歇性，並由具協同效應的結構重整集群所主導，其時空集群大小分佈服從冪律，臨界縮放指數為 -2.1。在恆定剪切下，本研究清楚觀測到源自 SR 中心的強烈波動傳播，其特徵為「快速縱向壓縮模式」與「慢速橫向剪切模式」的共存。至關至要的是，透過以個別 T1 轉換為中心的時空演變與系綜平均分析（ensemble-averaged analysis），本研究釐清了兩者的動態因果鏈結，發現單一結構重整能同時激發兩種波場，並在同時輻射出寬頻脈衝的四極橫向渦度場與強烈縱向坍縮核心。此發現為驅動固體中具備高度非各向同性（anisotropic）聲發射的微觀單粒子力學機制，提供了首個具備完整時空演變證據的直接實驗觀測。;When a driven solid yields under external stress， it undergoes intermittent stick-slip "quakes" that rapidly release accumulated elastic strain energy in the form of acoustic emission (AE) waves. From macroscopic tectonic faults to localized shear bands in metallic glasses， this plastic failure is fundamentally governed by a complex interplay between microscopic structural rearrangements (SRs) and acoustic wave (AW) propagation. However， conventional atomic and molecular systems are severely constrained by extreme sub-nanometer and femtosecond scales， rendering the direct observation of individual particle dynamics impossible. Although soft matter systems such as colloids or granules offer particle-resolved capabilities and have yielded many discoveries regarding structural soft spot predictions， shear band avalanches， and wave propagation， prior investigations have rarely focused on their real-space spatiotemporal evolution and direct causality. Consequently， establishing a causal link between a discrete， localized four-particle bond-exchange (T1 transition) event and the concurrent excitation， energy partitioning， and spatiotemporal radiation of both transverse and longitudinal emission fields remains an unexplored domain at the fundamental microscopic scale. To bridge this critical causal gap， this study utilizes a strongly coupled， two-dimensional (2D) dusty plasma crystal monolayer driven by stationary laser shear as an experimental analogue platform. Capitalizing on the macroscopic spatial scales and appropriately slowed-down temporal dynamics of levitated dust particles， we successfully track individual microscopic trajectories optically. Empirical Mode Decomposition (EMD) is then adaptively applied to real-space particle displacements， cleanly isolating non-stationary acoustic fluctuations from the dominant background shear flow. Our results demonstrate that plastic yielding within the sheared crystal exhibits distinct stick-slip intermittency mediated by cooperative SR clusters， which follow a power-law spatiotemporal size distribution with a critical scaling exponent of −2.1. Under constant shear， intense wave propagation originating from the SR center is clearly observed， characterized by the coexistence of fast longitudinal compressional modes and slow transverse shear modes. Crucially， through a spatiotemporal evolution and ensemble-averaged analysis centered around individual T1 transitions， this work uncovers the underlying dynamic causality. We demonstrate that a single structural rearrangement event concurrently excites both wave fields， simultaneously radiating a broadband impulsive transverse quadrupolar vorticity field and an intense longitudinal collapse core.
