# Charged Vortices in High Temperature Superconductors Probed by NMR

Source: [Charged Vortices in High Temperature Superconductors Probed by NMR](<https://www.sota2.com/research/paper/68fa25072c2a3760193abe2c>)

Collection index: [llms.txt](<https://www.sota2.com/research/llms.txt>)

Data updated: 2025-10-24T10:05:10.130Z

Authors: K. Kumagai, K. Nozaki, Yuji Matsuda

Published: 2000-12-28T10:16:17.000Z

## Abstract

We report a first experimental evidence that a vortex in the high temperature superconductors (HTSC) traps a finite electric charge from the high resolution measurements of the nuclear quadrupole frequencies. In slightly overdoped YBa\_2Cu\_3O\_7 the vortex is negatively charged by trapping electrons, while in underdoped YBa\_2Cu\_4O\_8 it is positively charged by expelling electrons. The sign of the trapped charge is opposite to the sign predicted by the conventional BCS theory. Moreover, in both materials, the deviation of the magnitude of the charge from the theory is also significant. These unexpected features can be attributed to the novel electronic structure of the vortex in HTSC.

## Recorded benchmark results

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## Original sources and implementation

[Original paper](<https://arxiv.org/abs/cond-mat/0012492>)

[PDF](<https://arxiv.org/pdf/cond-mat/0012492.pdf>)