Advanced

Simulation of Majorana Bound States in Multi-Band Josephson Junction Nanowires

Wolgast, Georg LU (2017) PHYM01 20161
Solid State Physics
Department of Physics
Abstract
Majorana bound states can be created at the ends of semiconducting nanowires using a combination of proximity-induced superconductivity, spin-orbit coupling and a magnetic eld. By adding a Josephson junction to this nanowire, four Majorana bound states can exist at the same time in the system. In this thesis I aim to examine the impact that the barrier in Josephson junctions has on the energy states in multi-band nanowires. This is done through simulations using a tight-binding model. The thesis will focus on how Majorana bound states
in the system will be influenced by different widths and heights of the Josephson junction barrier through calculations of the Majorana coupling energy and the energy gap to the nearest excited state. By... (More)
Majorana bound states can be created at the ends of semiconducting nanowires using a combination of proximity-induced superconductivity, spin-orbit coupling and a magnetic eld. By adding a Josephson junction to this nanowire, four Majorana bound states can exist at the same time in the system. In this thesis I aim to examine the impact that the barrier in Josephson junctions has on the energy states in multi-band nanowires. This is done through simulations using a tight-binding model. The thesis will focus on how Majorana bound states
in the system will be influenced by different widths and heights of the Josephson junction barrier through calculations of the Majorana coupling energy and the energy gap to the nearest excited state. By choosing a larger barrier width the system will require a smaller voltage to achieve four Majorana bound states, but be more susceptible to changes in the excited states. This result will only appear in multi-band models. The study indicates that Majorana bound states will behave differently in different energy bands and that the choice of barrier width is non-trivial in order to avoid influences from excited states. (Less)
Please use this url to cite or link to this publication:
author
Wolgast, Georg LU
supervisor
organization
course
PHYM01 20161
year
type
H2 - Master's Degree (Two Years)
subject
language
English
id
8905763
date added to LUP
2017-04-20 09:20:14
date last changed
2017-04-20 09:20:14
@misc{8905763,
  abstract     = {Majorana bound states can be created at the ends of semiconducting nanowires using a combination of proximity-induced superconductivity, spin-orbit coupling and a magnetic eld. By adding a Josephson junction to this nanowire, four Majorana bound states can exist at the same time in the system. In this thesis I aim to examine the impact that the barrier in Josephson junctions has on the energy states in multi-band nanowires. This is done through simulations using a tight-binding model. The thesis will focus on how Majorana bound states
in the system will be influenced by different widths and heights of the Josephson junction barrier through calculations of the Majorana coupling energy and the energy gap to the nearest excited state. By choosing a larger barrier width the system will require a smaller voltage to achieve four Majorana bound states, but be more susceptible to changes in the excited states. This result will only appear in multi-band models. The study indicates that Majorana bound states will behave differently in different energy bands and that the choice of barrier width is non-trivial in order to avoid influences from excited states.},
  author       = {Wolgast, Georg},
  language     = {eng},
  note         = {Student Paper},
  title        = {Simulation of Majorana Bound States in Multi-Band Josephson Junction Nanowires},
  year         = {2017},
}