Sökning: "impurity transport"

Visar resultat 31 - 35 av 43 avhandlingar innehållade orden impurity transport.

1. 31. Magnetotransport Studies of Mn Ion-Implanted Nanowires

   Författare :Waldomiro Paschoal; Linnaeus University; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; hopping conduction; ferromagnetism; ion-implantation; Nanowire; GaMnAs; magnetoresistance; Fysicumarkivet A:2014:Paschoal;

   Sammanfattning : This thesis focuses on the magnetotransport properties of highly Mn-doped crystalline GaAs nanowires. The GaAs nanowires were first grown by metal-organic vapor phase epitaxy from gold seed particles, and subsequently implanted with Mn ions under varying conditions, e.g., ion fluence and acceleration voltage. LÄS MER

3. 32. Magnetism of manganites, semiconductors and spin glasses

   Författare :Roland Mathieu; Ian Campbell; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materials science; Materialvetenskap; Materials science; Teknisk materialvetenskap; fasta tillståndets fysik; Solid State Physics;

   Sammanfattning : Magnetic and electrical properties of selected compounds containing manganese (Mn) are investigated by SQUID magnetometry and transport measurements.(Ga,Mn)As is a magnetic semiconductor obtained from GaAs by substituting Ga3+ for Mn2+. Mn acts in the alloy as a magnetic impurity, as well as a hole dopant. LÄS MER

4. 33. Tunneling Based Electronic Devices

   Författare :Erik Lind; Institutionen för elektro- och informationsteknik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; SiGe; Esaki Diodes; classical mechanics; quantum mechanics; relativity; termodynamik; relativitet; kvantmekanik; statistisk fysik; Matematisk och allmän teoretisk fysik; thermodynamics; gravitation; statistical physics; GaAs; Mathematical and general theoretical physics; Resonant Tunneling Permeable Base Transistors; Resonant Tunneling Diodes; klassisk mekanik; Fysicumarkivet A:2004:Lind;

   Sammanfattning : This thesis concerns different kinds of tunneling based devices all showing negative differential resistance. The thesis is divided in three parts, resonant tunneling transistors, Esaki diodes and coupled zero dimensional systems. LÄS MER

5. 34. Correlation Effects in One-dimensional Electron Systems

   Författare :Peter Sandström; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; exclusion statistics; resonant tunneling; one dimension; correlated electrons; charge quantization; persistent currents; Aharonov-Bohm effect; Luttinger liquid;

   Sammanfattning : Theoretical studies suggest that an interacting one-dimensional electron system does not behave as a Fermi liquid. Instead, it is predicted to form a Luttinger liquid characterized e.g. by the absence of fermionic quasiparticles and interaction-dependent power-laws for transport quantities. LÄS MER

7. 35. Collective Electron Dynamics in Mesoscopic Systems

   Författare :Oleksandr Zazunov; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Andreev reflection; Josephson effect; qubit; composite fermions; Andreev levels; resonant tunneling; superconductivity; high-T c superconductors; quantum point contact; fractional quantum Hall effect;

   Sammanfattning : This work is devoted to a theoretical investigation of collective electron dynamics in low dimensional materials and mesoscopic structures. A common feature of these studies is the focus on the properties of the low energy dynamics of conduction electrons. One class of studied materials is the high-Tc superconductor Nd2CuO4 and related compounds. LÄS MER