東華大學圖書館 |

Language: English

Help

回圖書館首頁

手機版館藏查詢

Back to Search results for [ subject:"Electromagnetics." ]

Switch To: Labeled | MARC Mode | ISBD

Electron transport in strong magneti...

Lambert, Nicholas John.

Linked to FindBook

Google Book

Amazon

博客來

Electron transport in strong magnetic field gradients.

Record Type:	Electronic resources : Monograph/item
Title/Author:	Electron transport in strong magnetic field gradients./
Author:	Lambert, Nicholas John.
Published:	Ann Arbor : ProQuest Dissertations & Theses, : 2007,
Description:	150 p.
Notes:	Source: Dissertations Abstracts International, Volume: 75-06, Section: C.
Contained By:	Dissertations Abstracts International75-06C.
Subject:	Electromagnetics. -
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=U601635
ISBN:	9781303569753

Electron transport in strong magnetic field gradients.
Lambert, Nicholas John.

Electron transport in strong magnetic field gradients. - Ann Arbor : ProQuest Dissertations & Theses, 2007 - 150 p.

Source: Dissertations Abstracts International, Volume: 75-06, Section: C.

Thesis (Ph.D.)--University of Bath (United Kingdom), 2007.

The physics of magnetic edge states and snake orbits in two dimensional electron gases (2DEGs) formed in Dy/AlGaAs/GaAs heterostructures is investigated. Such orbits are formed when a ferromagnetic stripe deposited on a semiconductor heterostructure is magnetised. The stray field from the stripe results in a gradient in the perpendicular component of the field at the 2DEG of the order of 10 6T/m. Magnetoresistance of a narrow, dry-etched, 2DEG channel subject to a high magnetic field gradient is investigated. The channel is shown to display positive, but asymmetric, magnetoresistance. A model is proposed in which positive and negative currents experience a different confining potential due to the field gradient. This alters the number of transverse current carrying modes in the channel, and so changes the channel conductivity. Devices we have termed snake state spectrometers have been fabricated and tested. These consist of point contacts positioned to discretised the snake orbits formed in a channel subject to a magnetic field gradient. A third point contact acts to selectively transmit snake orbits with appropriate orbital parameters. Using these devices, we have detected the transmission of discrete snake orbits. A theory is described in which electrons in snake orbits couple to the electromagnetic field. This results in conversion of electrical energy to microwaves. Preliminary experiments designed to test this theory led to the resistive detection of ferromagnetic resonance in the dysprosium stripe overlying the 2DEG.

ISBN: 9781303569753Subjects--Topical Terms:

3173223
Electromagnetics.
Subjects--Index Terms:

Electron transport

Electron transport in strong magnetic field gradients.
LDR:02519nmm a2200301 4500 001 2267344
005 20200623064734.5
008 220629s2007 ||||||||||||||||| ||eng d
020 $a 9781303569753
035 $a (MiAaPQ)AAIU601635
035 $a (MiAaPQ)RLUKUniversityofBath001578
035 $a AAIU601635
040 $a MiAaPQ $c MiAaPQ
100 1 $a Lambert, Nicholas John. $3 3544585
245 1 0 $a Electron transport in strong magnetic field gradients.
260 1 $a Ann Arbor : $b ProQuest Dissertations & Theses, $c 2007
300 $a 150 p.
500 $a Source: Dissertations Abstracts International, Volume: 75-06, Section: C.
500 $a Publisher info.: Dissertation/Thesis.
502 $a Thesis (Ph.D.)--University of Bath (United Kingdom), 2007.
520 $a The physics of magnetic edge states and snake orbits in two dimensional electron gases (2DEGs) formed in Dy/AlGaAs/GaAs heterostructures is investigated. Such orbits are formed when a ferromagnetic stripe deposited on a semiconductor heterostructure is magnetised. The stray field from the stripe results in a gradient in the perpendicular component of the field at the 2DEG of the order of 10 6T/m. Magnetoresistance of a narrow, dry-etched, 2DEG channel subject to a high magnetic field gradient is investigated. The channel is shown to display positive, but asymmetric, magnetoresistance. A model is proposed in which positive and negative currents experience a different confining potential due to the field gradient. This alters the number of transverse current carrying modes in the channel, and so changes the channel conductivity. Devices we have termed snake state spectrometers have been fabricated and tested. These consist of point contacts positioned to discretised the snake orbits formed in a channel subject to a magnetic field gradient. A third point contact acts to selectively transmit snake orbits with appropriate orbital parameters. Using these devices, we have detected the transmission of discrete snake orbits. A theory is described in which electrons in snake orbits couple to the electromagnetic field. This results in conversion of electrical energy to microwaves. Preliminary experiments designed to test this theory led to the resistive detection of ferromagnetic resonance in the dysprosium stripe overlying the 2DEG.
590 $a School code: 0690.
650 4 $a Electromagnetics. $3 3173223
653 $a Electron transport
690 $a 0607
710 2 $a University of Bath (United Kingdom). $b Department of Physics. $3 3544586
773 0 $t Dissertations Abstracts International $g 75-06C.
790 $a 0690
791 $a Ph.D.
792 $a 2007
793 $a English
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=U601635