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

Probing Topological Insulators and I...

Granstrom-Arndt, Christopher.

Linked to FindBook

Google Book

Amazon

博客來

Probing Topological Insulators and Itinerant Magnets at the Nano- and Atomic-Scale with Andreev Reflection Spectroscopy.

Record Type:	Electronic resources : Monograph/item
Title/Author:	Probing Topological Insulators and Itinerant Magnets at the Nano- and Atomic-Scale with Andreev Reflection Spectroscopy./
Author:	Granstrom-Arndt, Christopher.
Published:	Ann Arbor : ProQuest Dissertations & Theses, : 2018,
Description:	179 p.
Notes:	Source: Dissertation Abstracts International, Volume: 80-04(E), Section: B.
Contained By:	Dissertation Abstracts International80-04B(E).
Subject:	Low temperature physics. -
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=10937551
ISBN:	9780438681385

Probing Topological Insulators and Itinerant Magnets at the Nano- and Atomic-Scale with Andreev Reflection Spectroscopy.
Granstrom-Arndt, Christopher.

Probing Topological Insulators and Itinerant Magnets at the Nano- and Atomic-Scale with Andreev Reflection Spectroscopy. - Ann Arbor : ProQuest Dissertations & Theses, 2018 - 179 p.

Source: Dissertation Abstracts International, Volume: 80-04(E), Section: B.

Thesis (Ph.D.)--University of Toronto (Canada), 2018.

Low-temperature Andreev reflection (AR) spectroscopy measurements were performed on topological insulators, various compounds with atomically-smooth surfaces, a half-metallic manganite, and itinerant antiferromagnets. The purpose of these measurements was to expand the study of AR to include the various phenomena present in these materials.

ISBN: 9780438681385Subjects--Topical Terms:

3173917
Low temperature physics.

Probing Topological Insulators and Itinerant Magnets at the Nano- and Atomic-Scale with Andreev Reflection Spectroscopy.
LDR:03639nmm a2200349 4500 001 2202781
005 20190513114840.5
008 201008s2018 ||||||||||||||||| ||eng d
020 $a 9780438681385
035 $a (MiAaPQ)AAI10937551
035 $a (MiAaPQ)toronto:18331
035 $a AAI10937551
040 $a MiAaPQ $c MiAaPQ
100 1 $a Granstrom-Arndt, Christopher. $3 3429553
245 1 0 $a Probing Topological Insulators and Itinerant Magnets at the Nano- and Atomic-Scale with Andreev Reflection Spectroscopy.
260 1 $a Ann Arbor : $b ProQuest Dissertations & Theses, $c 2018
300 $a 179 p.
500 $a Source: Dissertation Abstracts International, Volume: 80-04(E), Section: B.
500 $a Adviser: John Y. T. Wei.
502 $a Thesis (Ph.D.)--University of Toronto (Canada), 2018.
520 $a Low-temperature Andreev reflection (AR) spectroscopy measurements were performed on topological insulators, various compounds with atomically-smooth surfaces, a half-metallic manganite, and itinerant antiferromagnets. The purpose of these measurements was to expand the study of AR to include the various phenomena present in these materials.
520 $a To understand the superconducting proximity effect that occurs across the c-axis interface of non-ideal three-dimensional topological insulators, we performed point-contact AR spectroscopy on Bi2X3 (X=Se,Te) single crystals with Nb tips at 4.2 K. Robust AR spectra were observed and analyzed with the Blonder-Tinkham-Klapwijk theory, taking into account tip-induced spin-orbit coupling, Fermi-surface mismatch, and the co-presence of bulk band and topological surface states at the Fermi level. Spectral analysis based on realistic band structures indicates that the superconductivity that can be proximity-induced into Bi2X3 is predominantly non-topological.
520 $a The spatial resolution of AR measurement was increased from the nano to the atomic scale by exploiting the resonant nature of d-wave AR for near-nodal junctions in the strong-barrier regime. Atomic-scale measurements of d-wave AR were achieved using YBa2Cu3 O7--delta (YBCO) single crystals as superconducting tips at 4.2 K, to form non-contact junctions on graphite, 2H-NbSe 2, and Bi2Se3. Differential conductance spectroscopy showed pronounced zero-bias peaks, characteristic of d-wave Andreev resonance, and whose heights were dependent on the spin-polarization of paramagnetic nickelate and half-metallic ferromagnetic manganite thin films. These results demonstrate that d-wave AR can potentially be used to study a variety of spin-based phenomena at the atomic scale.
520 $a To study how AR is affected by itinerant antiferromagnetism, we performed d-wave AR spectroscopy with YBCO to probe TiAu and variously-oxidized Nb (NbOx) samples. X-ray photoelectron spectroscopy was also used on the latter to measure their surface oxide composition. For NbOx, samples with a greater degree of oxidation exhibited greater suppression of d-wave AR features. For both TiAu and NbOx, low-impedance tip-sample junctions suppressed AR more than high-impedance junctions. AR suppression was also observed above the Neel temperature in both compounds, implying that spin fluctuations can suppress d-wave AR. Our data demonstrate that d-wave AR is suppressed by itinerant antiferromagnetism, and help identify suitable surface treatments of Nb when used in superconducting devices.
590 $a School code: 0779.
650 4 $a Low temperature physics. $3 3173917
650 4 $a Condensed matter physics. $3 3173567
650 4 $a Nanotechnology. $3 526235
690 $a 0598
690 $a 0611
690 $a 0652
710 2 $a University of Toronto (Canada). $b Physics. $3 3171865
773 0 $t Dissertation Abstracts International $g 80-04B(E).
790 $a 0779
791 $a Ph.D.
792 $a 2018
793 $a English
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=10937551