Sökning: "dark matter theory"

Visar resultat 11 - 15 av 37 avhandlingar innehållade orden dark matter theory.

1. 11. Microscopic Theory of Externally Tunable Exciton Signatures of Two-Dimensional Materials

   Författare :Maja Feierabend; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; localized states; density matrix formalism; magnetic field; transition metal dichalcogenides; Bloch equations; organic inorganic heterostructures; dark excitons; strain;

   Sammanfattning : Atomically thin transition metal dichalcogenides (TMDs) are in the focus of current research due to their efficient light-matter interaction and the remarkably strong Coulomb interaction that leads to tightly bound excitons. Due to their unique band structure, TMDs show a variety of bright and optically inaccessible dark excitonic states. LÄS MER

3. 12. Quantum Theory of Exciton-Exciton Interactions in Atomically Thin Semiconductors

   Författare :Daniel Erkensten; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; excitons; transition-metal dichalcogenides; many-body theory; van der Waals heterostructures; 2D materials;

   Sammanfattning : Atomically thin materials such as transition-metal dichalcogenides (TMDs) have emerged as an unprecedented platform for engineering future optoelectronic devices and studying exotic quantum phases of matter. In particular, the strong Coulomb interaction in these materials enables the formation of tightly-bound excitons, electron-hole pairs with neither purely fermionic nor bosonic character. LÄS MER

4. 13. Theory for superconducting few-photon detectors

   Författare :Mattias Jönsson; Jack Lidmar; Mats Wallin; Marcin Swillo; Karl Berggren; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Fysik; Physics;

   Sammanfattning : High-performance photon detectors are essential for fiber communication, which is the foundation of the modern internet. Emerging quantum information technologies, such as quantum key distribution, impose new requirements on the photon detectors used. LÄS MER

5. 14. Investigating the Dark Universe through Gravitational Lensing

   Författare :Teresa Riehm; Ariel Goobar; Edvard Mörtsell; Erik Zackrisson; Joachim Wambsganss; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; cosmology; gravitational lensing; dark matter; galaxies; galaxy clusters; Astronomy; Astronomi; Astronomy; astronomi;

   Sammanfattning : A variety of precision observations suggest that the present universe is dominated by some unknown components, the so-called dark matter and dark energy. The distribution and properties of these components are the focus of modern cosmology and we are only beginning to understand them. LÄS MER

7. 15. Cosmic tests of massive gravity

   Författare :Jonas Enander; Edvard Mörtsell; Stefan Hofmann; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Modified gravity; massive gravity; cosmology; dark energy; dark matter; fysik; Physics;

   Sammanfattning : Massive gravity is an extension of general relativity where the graviton, which mediates gravitational interactions, has a non-vanishing mass. The first steps towards formulating a theory of massive gravity were made by Fierz and Pauli in 1939, but it took another 70 years until a consistent theory of massive gravity was written down. LÄS MER