声子晶体中的声谷态输运  

Valley transport in sonic crystals

作　　者：邱春印[1] 陆久阳 刘正猷[1] 

机构地区：[1]武汉大学物理科学与技术学院,武汉430072

出　　处：《物理》2017年第1期21-28,共8页Physics

基　　金：国家自然科学基金(批准号:11374233;11674250)资助项目

摘　　要：如同自旋电子学中的自旋,固体中的能谷自由度可视为新的信息载体,从而用于未来的电子器件设计。最近,作者将谷态的概念引入到声子晶体中,揭示其涡旋属性并建立激发选择定则。有趣的是,声谷态可由外部声场直接激发,并通过探测声子晶体内外的声场分布展示其极化特性。这种涡旋手性锁定的谷输运将为人们提供全新的声波操控方式。考虑到声和物质的相互作用,也可预期谷涡旋态的其它新奇应用,如旋转操纵微颗粒等。进一步研究发现,存在两类拓扑非平庸的声谷霍尔相,它们之间的界面可以支持拓扑保护的边缘态。研究表明,该边缘态具备各种新颖的性质,如谷选择性激发、边界拐弯抗反射等。Like the spin in spintronics, the valley index in solid-state materials can be viewed as a new carder of information, which is useful for designing modern electronic devices. Recently, we have applied the concept of valleytronics to sonic crystals, revealed the vortex na- ture of valley states, and established valley-selection rules. Interestingly, the acoustic valley states can be stimulated directly by external sound, and detected through the field distributions inside and outside the crystal. The vortex chirality-locked valley transport enables a novel manipulation of sound. Considering the interaction between sound and matter, other fancy applications can also be anticipated for the valley vortex states, such as rotating micro-particles. In addition, we find that there exist two kinds of topologically distinct acoustic valley Hall phases, and an interface separating them can host topologically-protected edge states, associated with many exotic trans- port properties （such as valley selective excitations and antireflection in bent corners）.

关 键 词：声子晶体 狄拉克锥 声谷态 谷霍尔相变 拓扑谷输运 

分 类 号：O735[理学—晶体学]