Halon: A quasiparticle featuring critical charge fractionalization

  title={Halon: A quasiparticle featuring critical charge fractionalization},
  author={Kun Chen and Yu’an Huang and Youjin Deng and Boris Svistunov},
  journal={Physical Review B},
The halon is a special critical state of an impurity in a quantum-critical environment. The hallmark of the halon physics is that a well-defined integer charge gets fractionalized into two parts: a microscopic core with half-integer charge and a critically large halo carrying a complementary charge of $\pm 1/2$. The halon phenomenon emerges when the impurity--environment interaction is fine-tuned to the vicinity of a boundary quantum critical point (BQCP), at which the energies of two… 
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