论文标题
奇特的曲折对层中的奇数对密度相关性不足
Odd-frequency pair density wave correlations in underdoped cuprates
论文作者
论文摘要
库珀对与有限的质量中心动量确定的一对密度波最近在基于铜氧化物的高t $ _ \ textrm {c} $超导体（Cuprates）中观察到。电荷密度调制或波浪也普遍存在，在不足的铜矿中发现。在一般的平均场单波段模型中，我们表明电荷密度波和像丘比特（Cuprates）这样的$ d $波超导体中的均匀超导性的共存，除了偶数频率的对应物外，还会产生一个奇怪的频率自旋旋转密度波。诱导的奇数对密度波的强度取决于电荷密度波的调制波矢量，奇数频对密度波甚至与布里素区域部分的频率相当。我们表明，电荷密度波的调制波向量从双轴到单轴的变化可以增强对密度波的奇数频率成分。超导性和单轴电荷密度波的这种共存已经在不足的酸奶油中的高磁场上进行了实验验证。我们进一步讨论了适用于铁基密度波和旋转密度波的共存状态中产生的奇数自旋三对密度波的可能性，适用于基于铁的超导体。因此，我们的工作为高t $ _c $超导体提供了散装奇数超导的途径。
Pair density waves, identified by Cooper pairs with finite center-of-mass momentum, have recently been observed in copper oxide based high T$_\textrm{c}$ superconductors (cuprates). A charge density modulation or wave is also ubiquitously found in underdoped cuprates. Within a general mean-field one-band model we show that the coexistence of charge density waves and uniform superconductivity in $d$-wave superconductors like cuprates, generates an odd-frequency spin-singlet pair density wave, in addition to the even-frequency counterparts. The strength of the induced odd-frequency pair density wave depends on the modulation wave vector of the charge density wave, with the odd-frequency pair density waves even becoming comparable to the even-frequency ones in parts of the Brillouin zone. We show that a change in the modulation wave vector of the charge density wave from bi-axial to uni-axial, can enhance the odd-frequency component of the pair density waves. Such a coexistence of superconductivity and uni-axial charge density wave has already been experimentally verified at high magnetic fields in underdoped cuprates. We further discuss the possibility of an odd-frequency spin-triplet pair density wave generated in the coexistence regime of superconductivity and spin density waves, applicable to the iron-based superconductors. Our work thus presents a route to bulk odd-frequency superconductivity in high T$_c$ superconductors.
