论文标题
由于疾病而引起的莫特状态阻尼的激发的出现
Emergence of damped-localized excitations of the Mott state due to disorder
论文作者
论文摘要
深度光晶格电势井中超速剂量量子气的一个关键方面是实现了强烈相互作用的莫特绝缘阶段。这一阶段的许多特征是充分理解的，但是对于随机外部电势对其张开的准粒子和Quasihole低能激发的影响知之甚少。在本研究中，我们研究了疾病对莫特（Mott）绝缘状态激发的影响，该温度在零温度下描述的零温度。使用现场理论方法，我们获得了光谱函数的疾病集合平均值的重新介绍。它的分析表明，疾病导致准粒子和Quasihole兴奋的有效质量增加。此外，它产生了阻尼状态的出现，在空间中传播过程中呈指数衰减，并在混乱与相互作用相媲美时占主导地位。我们认为，这种阻尼全定位的状态对应于玻色玻璃相的单粒子激发。
A key aspect of ultracold bosonic quantum gases in deep optical lattice potential wells is the realization of the strongly interacting Mott insulating phase. Many characteristics of this phase are well understood, however little is known about the effects of a random external potential on its gapped quasiparticle and quasihole low-energy excitations. In the present study we investigate the effect of disorder upon the excitations of the Mott insulating state at zero temperature described by the Bose-Hubbard model. Using a field-theoretical approach we obtain a resummed expression for the disorder ensemble average of the spectral function. Its analysis shows that disorder leads to an increase of the effective mass of both quasiparticle and quasihole excitations. Furthermore, it yields the emergence of damped states, which exponentially decay during propagation in space and dominate the whole band when disorder becomes comparable to interactions. We argue that such damped-localized states correspond to single-particle excitations of the Bose-glass phase.
