论文标题
使用腔机电的超导涡流测量
Superconducting vortex-charge measurement using cavity electromechanics
论文作者
论文摘要
当磁场穿透超导体的表面时，它会导致磁通涡流的形成。据预测，通量涡流将具有带电的涡旋芯并创建一个二型电场。在High-T $ _C $超导体（HTS）中，这种充电捕获在涡流中的增强尤其增强。在这里，我们集成了由hts bi $ _2 $ _2 $ _2 $ cacu $ _2 $ _2 $ o $ _ {8+δ} $制成的机械谐振器，以实现腔 - 电动机机械设备。由于基于腔的设备对外部力的灵敏度的敏感性，我们通过测量机械谐振器的机电响应直接检测到通量涡流中的电荷。我们的测量结果揭示了由于单个涡流核心约为30〜 $ | e | a_b $，表面电偶极矩的强度，相当于每铜的涡流费用$ _2 $ 3.7 \ $ 3.7 \ times 10^{ - 2} { - 2} | e | $，如果$ a_b $是$ a_b $，则是bohr radius and $ e $。
As the magnetic field penetrates the surface of a superconductor, it results in the formation of flux-vortices. It has been predicted that the flux-vortices will have a charged vortex core and create a dipolelike electric field. Such a charge trapping in vortices is particularly enhanced in high-T$_c$ superconductors (HTS). Here, we integrate a mechanical resonator made of a thin flake of HTS Bi$_2$Sr$_2$CaCu$_2$O$_{8+δ}$ into a microwave circuit to realize a cavity-electromechanical device. Due to the exquisite sensitivity of cavity-based devices to the external forces, we directly detect the charges in the flux-vortices by measuring the electromechanical response of the mechanical resonator. Our measurements reveal the strength of surface electric dipole moment due to a single vortex core to be approximately 30~$|e|a_B$, equivalent to a vortex charge per CuO$_2$ layer of $3.7\times 10^{-2}|e|$, where $a_B$ is the Bohr radius and $e$ is the electronic charge.
