Sökning: "mesa structures"

Visar resultat 6 - 10 av 13 avhandlingar innehållade orden mesa structures.

  1. 6. Intrinsic tunneling spectroscopic investigations of Bi2Sr2CaCu2O8+x superconductors : The fluxon lattice, resonant phenomena,flux-flow and current doping

    Författare :Holger Motzkau; Vladimir M. Krasnov; Paul Müller; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : In this thesis, the tunneling between individual atomic layers in structures of Bi2Sr2CaCu2O8+x based high-temperature superconductors are experimentally studied employing the intrinsic Josephson effect. A special attention is paid on the fabrication of small mesa structures using micro and nanofabrication techniques. LÄS MER

  3. 7. Metall organic vapour phase epitaxy for advanced III-V devices

    Författare :Nils Nordell; Sture Petersson; Gunnar Landgren; Ferdinand Scholz; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Metalorganic vapour phase epitaxy MOVPE ; III-V compound semiconductors; epitaxial uniformity; p-type doping profiles; epitaxial regrowth; chlorine-MOVPE; buried heterostructure laser; heterostructure bipolar transistor; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : Metalorganic vapour phase epitaxy (MOVPE) has proven to be a successful method for growth of structures for advanced optoelectronic semiconductor devices in III-V compounds. This thesis deals with technological and process related aspects of MOVPE from an experimental perspective. LÄS MER

  4. 8. Intrinsic tunneling spectroscopy of low-Tc cuprate superconductors : Pseudogap, fluctuations and electrical doping

    Författare :Thorsten Jacobs; Vladimir M. Krasnov; Magnus Andersson; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Bi-2201; Bi-2212; low-Tc; cuprates; intrinsic tunneling; transport measurements; pseudogap; fluctuations; electrical doping; Physics; fysik;

    Sammanfattning : In this thesis, intrinsic tunneling and magnetic transport measurements of the cuprate superconductor Bi2+xSr2-yCuO6+δ (Bi-2201) are presented. The compound is characterized by a single-CuO2 plane, has a very low critical temperature Tc ~ 4K and a relatively low upper critical field Hc2 ~ 10T. LÄS MER

  5. 9. High performance materials and processing technology for uncooled 1.3 μm laser diodes

    Författare :Roberta Campi; Gunnar Landgren; Abdallah Ougazzaden; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; MOCVD; InGaAsP; AlGaInAsP; AlGaInAs; In-situ etching; TBCI; Semiconductor physics; Halvledarfysik;

    Sammanfattning : This thesis investigates different material systems and processing technology for high temperature compatible laser diodes used in volume applications within the 1.3-μm telecom wavelength window. LÄS MER

  7. 10. Type-II interband quantum dot photodetectors

    Författare :Oscar Gustafsson; Mattias Hammar; Wenquan Ma; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; photodetector; quantum dot; infrared; MOVPE; thermal imaging; type-II; photoluminescence; III V; InSb; InGaSb; InAs; SRA - ICT; SRA - Informations- och kommunikationsteknik;

    Sammanfattning : Photon detectors based on single-crystalline materials are of great interest for high performance imaging applications due to their low noise and fast response. The major detector materials for sensing in the long-wavelength infrared (LWIR) band (8-14 µm) are currently HgCdTe (MCT) and AlGaAs/GaAs quantum wells (QW) used in intraband-based quantum-well infrared photodetectors (QWIPs). LÄS MER