Avancerad sökning

Hittade 4 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Spatiotemporal carrier dynamics in graphene

    Författare :Roland Jago; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; spatiotemporal dynamics; density matrix formalism; graphene; relaxation dynamics; carrier multiplication; Bloch equations; photoconduction effect; bolometric effect;

    Sammanfattning : Graphene as an atomically thin material exhibits remarkable optical and electronic properties that suggest its technological application in novel optoelectronic devices, such as graphene-based photodetectors and lasers. To understand the properties of such devices on a microscopic level, we study the interplay of optical excitation, carrier-carrier, carrier-phonon, and carrierphoton scattering as well as diffusion processes. LÄS MER

  3. 2. Horizontal Slot Waveguides for Silicon Photonics Back-End Integration

    Författare :Maziar A. M. Naiini; Mikael Östling; Jörge Schulze; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; silicon photonics; slot waveguides; grating couplers; CMOS tech- nology; high-k; ALD; germanium photodetectors; graphene photodetectors; pho- tonic integrated circuits;

    Sammanfattning : This thesis presents the development of integrated silicon photonic devices. These devices are compatible with the present and near future CMOS technology. High-khorizontal grating couplers and waveguides are proposed. LÄS MER

  4. 3. Electron dynamics in graphene in the presence of an electrical field

    Författare :Roland Jago; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Bloch equations; density matrix formalism; graphene; relaxation dynamics; photoconduction effect; carrier multiplication;

    Sammanfattning : Graphene as atomically thin two-dimensional material exhibits remarkableoptical and electronic properties that suggest its technological applicationin novel optoelectronic devices, such as graphene-based lasers and photodetectors.The linear electronic bandstructure and the vanishing band gap atthe Dirac point open up new relaxation channels, such as Auger scattering. LÄS MER

  5. 4. Integration of Two-Dimensional Materials for Electronics and Photonics

    Författare :Arne Quellmalz; Kristinn Gylfason; Frank Niklaus; Cedric Huyghebaert; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : Two-dimensional (2D) materials with a thickness on the atomic scale promise to continue the trend of increasing performance in electronics, photonics, and sensing. However, despite record-breaking demonstrations of individual devices, the commercial exploitation of 2D materials is still limited. LÄS MER