论文标题
分形超流体。 (ii)。凝结细分颗粒
Fractonic superfluids. (II). Condensing subdimensional particles
论文作者
论文摘要
在本文中,我们在$ d $维空间中开发了异国情调的分形超流相期,在该空间中,有效的粒子 - 其迁移率是\ emph {部分}限制的 - 被凝结。研究了非对角线长距离顺序(ODLRO)。为了证明,我们考虑了“ lineons” - 一种差异粒子,其迁移率仅在某些一维方向上是免费的。我们从$ d $组成的微观哈密顿模型开始。该模型尊重更高的对称性,使得每个组件的粒子数和角电荷矩都是保守的量。通过执行Hartree-fock-Bogoliubov近似,我们得出了一组Gross-Pitaevskii方程和Bogoliubov-De Gennes(BDG)Hamiltonian,这导致了对Gapless Phonons和Gapped Rotons的统一描述。借助相干路径 - 综合表示,我们还得出了无间隙金矿模式的长波长有效场理论,并分析了经典基础状态周围的量子波动。还研究了Euler-Lagrange方程和Noether电荷/电流。在两个空间维度和更高的空间维度中,这种ODLRO在量子波动上保持稳定。最后,我们研究涡旋配置。较高的对称性实施了点涡流激发的层次结构,其结构由两个指导语句主导。特别是,我们构建了两种类型的涡流激发,即常规和偶极涡流。后者带有尺寸为动量的电荷。这两个语句可以更普遍地适用。讨论了几个未来的方向。
In this paper, we develop an exotic fractonic superfluid phase in $d$-dimensional space where subdimensional particles -- their mobility is \emph{partially} restricted -- are condensed. The off-diagonal long range order (ODLRO) is investigated. To demonstrate, we consider "lineons" -- a subdimensional particle whose mobility is free only in certain one-dimensional directions. We start with a $d$-component microscopic Hamiltonian model. The model respects a higher-rank symmetry such that both particle numbers of each component and angular charge moments are conserved quantities. By performing the Hartree-Fock-Bogoliubov approximation, we derive a set of Gross-Pitaevskii equations and a Bogoliubov-de Gennes (BdG) Hamiltonian, which leads to a unified description of gapless phonons and gapped rotons. With the coherent-path-integral representation, we also derive the long-wavelength effective field theory of gapless Goldstone modes and analyze quantum fluctuations around classical ground states. The Euler-Lagrange equations and Noether charges/currents are also studied. In two spatial dimensions and higher, such an ODLRO stays stable against quantum fluctuations. Finally, we study vortex configurations. The higher-rank symmetry enforces a hierarchy of point vortex excitations whose structure is dominated by two guiding statements. Specially, we construct two types of vortex excitations, the conventional and dipole vortices. The latter carries a charge with dimension as a momentum. The two statements can be more generally applicable. Several future directions are discussed.