@article {ISI:000457058500007,
title = {Fractional Josephson effect with and without Majorana zero modes},
journal = {Phys. Rev. B},
volume = {99},
number = {3},
year = {2019},
month = {JAN 29},
pages = {035312},
publisher = {AMER PHYSICAL SOC},
type = {Article},
abstract = {It is known that the low-energy physics of the Josephson effect in the presence of Majorana zero modes exhibits a 4 pi periodicity as the Aharonov-Bohm flux varies in contrast to the 2 pi Josephson periodicity in usual superconducting junctions. We study this fractional Josephson effect in one-dimensional topological superconductors in Majorana nanowire systems by focusing on the features of the phase-energy relations in a superconducting semiconductor nanowire with spin-orbital coupling by including different factors operational in experimental systems, such as short wire length, suppression of superconducting gap, and the presence of an Andreev bound state. We show that even in the absence of the Majorana zero modes, some nontopological physical effects can manifest a 4 pi periodicity of the phase-energy relation in the Josephson junction, thus providing an alternative physics for fractional Josephson effect with no underlying Majorana zero modes. Furthermore, we consider several scenarios of inhomogeneous chemical potential distributions in the superconducting nanowire leading to four Majorana bound states and construct the effective four-Majorana model to correctly describe the low-energy theory of the Josephson effect. In this setup, multiple Majorana zero modes can also have the 4 pi fractional Josephson effect, although the underlying physics arises from Andreev bound states since two close-by Majorana bound states effectively form Andreev bound states. Our work demonstrates that the mere observation of a fractional Josephson effect simulating 4 pi periodicity might not, by itself, be taken as the definitive evidence for topological superconductivity. This finding has important implications for the ongoing search for non-Abelian Majorana zero modes and efforts for developing topological qubits.},
issn = {2469-9950},
doi = {10.1103/PhysRevB.99.035312},
author = {Chiu, Ching-Kai and S. Das Sarma}
}
@article { ISI:000496588600002,
title = {Protocol for Reading Out Majorana Vortex Qubits and Testing Non-Abelian Statistics},
journal = {Phys. Rev. Appl.},
volume = {12},
number = {5},
year = {2019},
month = {NOV 14},
pages = {054035},
publisher = {AMER PHYSICAL SOC},
type = {Article},
abstract = {The successful testing of non-Abelian statistics not only serves as a milestone in fundamental physics but also provides a quantum-gate operation in topological quantum computation. An accurate and efficient readout scheme of a topological qubit is an essential step toward the experimental confirmation of non-Abelian statistics. In the current work, we propose a protocol to read out the quantum state of a Majorana vortex qubit on a topological superconductor island. The protocol consists of four Majorana zero modes trapped in spatially well-separated vortex cores on the two-dimensional surface of a Coulomb blockaded topological superconductor. Our proposed measurement is implemented by a pair of weakly coupled Majorana modes separately in touch with two normal-metal leads and the readout is realized by observing the conductance-peak location in terms of the gate voltage. Using this protocol, we can further test the non-Abelian statistics of Majorana zero modes in the two-dimensional platform. A successful readout of a Majorana qubit is a crucial step toward the future application of topological quantum computation. In addition, this Coulomb-blockaded setup can distinguish Majorana zero modes from Caroli-de Gennes-Matricon modes in vortex cores.},
issn = {2331-7019},
doi = {10.1103/PhysRevApplied.12.054035},
author = {Liu, Chun-Xiao and Liu, Dong E. and Zhang, Fu-Chun and Chiu, Ching-Kai}
}
@article { ISI:000445336700001,
title = {Chiral Majorana fermion modes on the surface of superconducting topological insulators},
journal = {EPL},
volume = {123},
number = {4},
year = {2018},
month = {AUG},
pages = {47005},
issn = {0295-5075},
doi = {10.1209/0295-5075/123/47005},
author = {Chiu, Ching-Kai and Bian, Guang and Zheng, Hao and Yin, Jia-Xin and Zhang, Songtian S. and Sanchez, D. S. and Belopolski, I and Xu, Su-Yang and Hasan, M. Zahid}
}
@article { ISI:000423428400002,
title = {Conductance interference in a superconducting Coulomb blockaded Majorana ring},
journal = {PHYSICAL REVIEW B},
volume = {97},
number = {3},
year = {2018},
month = {JAN 26},
pages = {035310},
issn = {2469-9950},
doi = {10.1103/PhysRevB.97.035310},
author = {Chiu, Ching-Kai and Sau, Jay D. and S. Das Sarma}
}
@article { ISI:000443395600003,
title = {Helical Majorana edge mode in a superconducting antiferromagnetic quantum spin Hall insulator},
journal = {PHYSICAL REVIEW B},
volume = {98},
number = {8},
year = {2018},
month = {AUG 31},
pages = {081412},
issn = {2469-9950},
doi = {10.1103/PhysRevB.98.081412},
author = {Huang, Yingyi and Chiu, Ching-Kai}
}
@article { ISI:000406910800004,
title = {Conductance of a superconducting Coulomb-blockaded Majorana nanowire},
journal = {PHYSICAL REVIEW B},
volume = {96},
number = {5},
year = {2017},
month = {AUG 4},
issn = {2469-9950},
doi = {10.1103/PhysRevB.96.054504},
author = {Chiu, Ching-Kai and Sau, Jay D. and S. Das Sarma}
}
@article { ISI:000376250800005,
title = {Ca3P2 and other topological semimetals with line nodes and drumhead surface states},
journal = {PHYSICAL REVIEW B},
volume = {93},
number = {20},
year = {2016},
month = {MAY 17},
issn = {2469-9950},
doi = {10.1103/PhysRevB.93.205132},
author = {Chan, Y. -H. and Chiu, Ching-Kai and Chou, M. Y. and Schnyder, Andreas P.}
}
@article { ISI:000383053400001,
title = {Classification of topological quantum matter with symmetries},
journal = {REVIEWS OF MODERN PHYSICS},
volume = {88},
number = {3},
year = {2016},
month = {AUG 31},
issn = {0034-6861},
doi = {10.1103/RevModPhys.88.035005},
author = {Chiu, Ching-Kai and Teo, Jeffrey C. Y. and Schnyder, Andreas P. and Ryu, Shinsei}
}
@article { ISI:000372799400003,
title = {Drumhead surface states and topological nodal-line fermions in TlTaSe2},
journal = {PHYSICAL REVIEW B},
volume = {93},
number = {12},
year = {2016},
month = {MAR 28},
issn = {2469-9950},
doi = {10.1103/PhysRevB.93.121113},
author = {Bian, Guang and Chang, Tay-Rong and Zheng, Hao and Velury, Saavanth and Xu, Su-Yang and Neupert, Titus and Chiu, Ching-Kai and Huang, Shin-Ming and Sanchez, Daniel S. and Belopolski, Ilya and Alidoust, Nasser and Chen, Peng-Jen and Chang, Guoqing and Bansil, Arun and Jeng, Horng-Tay and Lin, Hsin and Hasan, M. Zahid}
}
@article { ISI:000383235000012,
title = {Induced spectral gap and pairing correlations from superconducting proximity effect},
journal = {PHYSICAL REVIEW B},
volume = {94},
number = {12},
year = {2016},
month = {SEP 6},
issn = {2469-9950},
doi = {10.1103/PhysRevB.94.125304},
author = {Chiu, Ching-Kai and Cole, William S. and S. Das Sarma}
}