Magnetically controlled chemical potential in field effect devices

No Thumbnail Available
Change log
Ciccarelli, Chiara 

In this thesis I describe a sensitive technique for quantifying the chemical potential anisotropy of magnetically ordered and spin-orbit coupled materials. An aluminium single electron transistor (SET) lithographically fabricated on top of a magnetic gate is used to characterise the chemical potential anisotropy of Ga0 .97Mno. 03As and Gao.941\1no.o6As. The conductance variation of the SET provides a direct probe of the magnetisation-dependent change in the chemical potential of the magnetic gate with ?eV resolution. The control of the SET conductance by the magnetisation direction of the gate opens the way to a new recording mechanism. Achieving the same control in a semiconductor device represents a first step towards possible applications in computer memories. In the second part of my work I present the measurements on a CoPt gated metal-oxide-semiconductor� field effect transistor. In the last part of my thesis, I present a study of the response of a metal SET to a radio-frequency perturbation, which showed the conditions of maximum sensitivity and set a lower limit to the detection bandwidth of the SET. This study is important for assessing the performance of a prototypical device for detecting fast magnetisation switching or for quantifying the chemical potential anisotropy of magnetic nano-structures that cannot be electrically connected to an electrode, but that are still expected to have interesting anisotropic properties


This thesis is not available on this repository until the author agrees to make it public. If you are the author of this thesis and would like to make your work openly available, please contact us:

Cambridge University Library can make a copy of this work available only for the purposes of private study and non-commercial research. Copies should not be shared or saved in any shared facilities. Copyright over the content of these works is with their authors. Theses from the Library collection are considered unpublished works and according to UK legislation quoting from them is not allowed without permission from their author.

If you can commit to these terms, please complete the request form which you can find through this link:

Please note that print copies of theses may be available for consultation in the Cambridge University Library's Manuscript reading room. Admission details are at

Doctor of Philosophy (PhD)
Awarding Institution
University of Cambridge