東華大學圖書館 |

Language: English

Help

回圖書館首頁

手機版館藏查詢

Back

Switch To: Labeled | MARC Mode | ISBD

Transport Properties of Topological ...

Knez, Ivan.

Linked to FindBook

Google Book

Amazon

博客來

Transport Properties of Topological Phases in Broken Gap Indium Arsenide/Gallium Antimonide Based Quantum Wells.

Record Type:	Electronic resources : Monograph/item
Title/Author:	Transport Properties of Topological Phases in Broken Gap Indium Arsenide/Gallium Antimonide Based Quantum Wells./
Author:	Knez, Ivan.
Description:	138 p.
Notes:	Source: Dissertation Abstracts International, Volume: 73-11(E), Section: B.
Contained By:	Dissertation Abstracts International73-11B(E).
Subject:	Condensed matter physics. -
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3524522
ISBN:	9781267539113

Transport Properties of Topological Phases in Broken Gap Indium Arsenide/Gallium Antimonide Based Quantum Wells.
Knez, Ivan.

Transport Properties of Topological Phases in Broken Gap Indium Arsenide/Gallium Antimonide Based Quantum Wells. - 138 p.

Source: Dissertation Abstracts International, Volume: 73-11(E), Section: B.

Thesis (Ph.D.)--Rice University, 2012.

This item must not be sold to any third party vendors.

The quantum Spin Hall Insulator (QSHI) is a two-dimensional variant of a novel class of materials characterized by topological order, whose unique properties have recently triggered much interest and excitement in the condensed matter community. Most notably, the topological properties of these systems hold great promise in mitigating the difficult problem of decoherence in implementations of quantum computers. Although QSHI has been theoretically predicted in a few different materials, prior to the work presented in this thesis, only the HgTe/CdTe semiconductor system has shown direct evidence for the existence of this phase. Ideally insulating in the bulk, QSHI is characterized by one-dimensional channels at the sample perimeter, which have a helical property, with carrier spin tied to the carrier direction of motion, and protected from elastic back-scattering by time-reversal symmetry. In this thesis we present low temperature transport measurements, showing strong evidence for the existence of proposed helical edge channels in InAs/CaSb quantum wells, which thus emerge as an important alternate to HgTe/CdTe quantum wells in studies of two-dimensional topological insulators and superconductors. Surprisingly, edge modes persist in spite of comparable bulk conduction of non-trivial origin and show only weak dependence on magnetic field in mesoscopic devices. We elucidate that the seeming independence of edge on bulk transport comes due to the disparity in Fermi wave-vectors between the bulk and the edge, leading to a total internal reflection of the edge modes. Furthermore, low Schottky barrier of this material system and good interface to superconductors allows us to probe topological properties of helical channels in Andreev reflection measurements, opening a promising route towards the realization of topologically superconducting phases hosting exotic Majorana modes.

ISBN: 9781267539113Subjects--Topical Terms:

3173567
Condensed matter physics.

Transport Properties of Topological Phases in Broken Gap Indium Arsenide/Gallium Antimonide Based Quantum Wells.
LDR:02949nmm a2200301 4500 001 2061151
005 20150929074112.5
008 170521s2012 ||||||||||||||||| ||eng d
020 $a 9781267539113
035 $a (MiAaPQ)AAI3524522
035 $a AAI3524522
040 $a MiAaPQ $c MiAaPQ
100 1 $a Knez, Ivan. $3 3175383
245 1 0 $a Transport Properties of Topological Phases in Broken Gap Indium Arsenide/Gallium Antimonide Based Quantum Wells.
300 $a 138 p.
500 $a Source: Dissertation Abstracts International, Volume: 73-11(E), Section: B.
500 $a Adviser: Rui-Rui Du.
502 $a Thesis (Ph.D.)--Rice University, 2012.
506 $a This item must not be sold to any third party vendors.
506 $a This item must not be added to any third party search indexes.
520 $a The quantum Spin Hall Insulator (QSHI) is a two-dimensional variant of a novel class of materials characterized by topological order, whose unique properties have recently triggered much interest and excitement in the condensed matter community. Most notably, the topological properties of these systems hold great promise in mitigating the difficult problem of decoherence in implementations of quantum computers. Although QSHI has been theoretically predicted in a few different materials, prior to the work presented in this thesis, only the HgTe/CdTe semiconductor system has shown direct evidence for the existence of this phase. Ideally insulating in the bulk, QSHI is characterized by one-dimensional channels at the sample perimeter, which have a helical property, with carrier spin tied to the carrier direction of motion, and protected from elastic back-scattering by time-reversal symmetry. In this thesis we present low temperature transport measurements, showing strong evidence for the existence of proposed helical edge channels in InAs/CaSb quantum wells, which thus emerge as an important alternate to HgTe/CdTe quantum wells in studies of two-dimensional topological insulators and superconductors. Surprisingly, edge modes persist in spite of comparable bulk conduction of non-trivial origin and show only weak dependence on magnetic field in mesoscopic devices. We elucidate that the seeming independence of edge on bulk transport comes due to the disparity in Fermi wave-vectors between the bulk and the edge, leading to a total internal reflection of the edge modes. Furthermore, low Schottky barrier of this material system and good interface to superconductors allows us to probe topological properties of helical channels in Andreev reflection measurements, opening a promising route towards the realization of topologically superconducting phases hosting exotic Majorana modes.
590 $a School code: 0187.
650 4 $a Condensed matter physics. $3 3173567
650 4 $a Nanoscience. $3 587832
690 $a 0611
690 $a 0565
710 2 $a Rice University. $3 960124
773 0 $t Dissertation Abstracts International $g 73-11B(E).
790 $a 0187
791 $a Ph.D.
792 $a 2012
793 $a English
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3524522