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Electron Tunneling Spectroscopy of the Kitaev Quantum Spin Liquid Sandwiched with Superconductors

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 نشر من قبل Liang-Jian Zou
 تاريخ النشر 2021
  مجال البحث فيزياء
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We present the electron tunneling transport and spectroscopic characters of a superconducting Josephson junction with a barrier of single Kitaev quantum spin liquid (QSL) layer. We find that the dynamical spin correlation features are well reflected in the direct current differential conductance dI_c/dV of the single-particle tunneling with an energy shift of superconducting gap sum 2{Delta}, including the unique spin gap and dressed itinerant Majorana dispersive band, which can be regarded as evidence of the Kitaev QSL. However, the zero-voltage Josephson current I_s only displays some residual features of dynamical spin susceptibility in the Kitaev QSL due to the spin singlet of Cooper pairs. These results pave a new way to measure the dynamical spinon or Majorana fermion spectroscopy of the Kitaev and other spin liquid materials.


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