Sökning: "quantum physics"

Visar resultat 31 - 35 av 289 uppsatser innehållade orden quantum physics.

1. 31. Communication and Error Correction via Polarisation of Single Photons and Time Ordering

   Master-uppsats, KTH/Tillämpad fysik

   Författare :Shek Lun Leung; [2023]
   Nyckelord :Quantum Technology; Physics; Photon; Telecommunication; polarization; time ordering; BPPM; PPM; OOK; Simulation; quantum communication; Kvantteknologi; Fysik; Foton; Telekommunikation; polarisering; tidsordning; BPPM; PPM; OOK; Simulering; kvantkommunikation; satellite communication;

   Sammanfattning : This research study aims to investigate the capacity of single photons to carry information through polarization and time ordering and proposes a protocol called Beyond Pulse Position Modulation (BPPM) to improve photon-based communication reliability over longer distances with limited power. Such a protocol may be used in any communication scenario where energy efficiency is important, e. LÄS MER

3. 32. Time-dependent light-matter coupling and quantum dynamics

   Kandidat-uppsats, Lunds universitet/Matematisk fysik; Lunds universitet/Fysiska institutionen

   Författare :Daniel Elgbro; [2023]
   Nyckelord :light-matter interaction; Rabi oscillations; quantum dynamics; optical cavity; qubit; coupled qubit; coupling strength; time-dependent coupling; dynamical qubits; entanglement; concurrence; qubit state manipulation; Jaynes-Cummings; Tavis-Cummings; Physics and Astronomy;

   Sammanfattning : In this thesis, two quantum dynamical system’s of one and two qubits coupled to a field mode confined in an optical cavity have been studied. Within the Jaynes- and Tavis- Cummings model, the dynamics of the corresponding light-matter interaction was defined in terms of the system’s coupling constants. LÄS MER

4. 33. Gravitational Decoherence in Macroscopic Quantum Systems

   Kandidat-uppsats, Uppsala universitet/Teoretisk fysik

   Författare :Niklas Engelhardt Önne; [2023]
   Nyckelord :decoherence; gravitational decoherence; quantum mechanics; quantum physics; macroscopic quantum mechanics; macroscopic quantum physics; gravity; general relativity; gravitational time dilation; quantum-to-classical transition; nonrelativistic quantum mechanics; quantum gravity; dekoherens; gravitationell dekoherens; kvantmekanik; kvantfysik; makroskopisk kvantmekanik; makroskopisk kvantfysik; gravitation; allmän relativitetsteori; gravitationell tidsdilatation; övergången från kvantfysik till klassisk fysik; ickerelativistisk kvantmekanik; kvantgravitation;

   Sammanfattning : The problem of how quantum mechanics gives rise to classicality has been debated for more than a century. A commonly proposed solution is decoherence, i.e. the gradual decay of superpositions in open quantum systems due to their inevitable interaction with their environment. LÄS MER

5. 34. Beyond the Gross-Pitaevskii Equation: A Perturbative Approach

   Master-uppsats, Lunds universitet/Fysiska institutionen; Lunds universitet/Teknisk fysik (CI)

   Författare :Anton Johansson; [2023]
   Nyckelord :Gross-Pitaevskii; Beyond mean-field; Many-body Perturbation Theory; Bose-Einstein Condensate; BEC; Physics and Astronomy;

   Sammanfattning : We propose and implement a beyond Gross-Pitaevskii approach based on Many-Body Perturbation theory (MBPT) for the study of Bose-Einstein Condensate (BECs) ground states. Two partitions of the system Hamiltonian are considered. LÄS MER

7. 35. Characterization of Bi-incorporated InSb(111)A/B Surfaces : An STM and XPS Study

   Master-uppsats, Lunds universitet/Synkrotronljusfysik; Lunds universitet/Fysiska institutionen

   Författare :Shengpeng Huang; [2023]
   Nyckelord :indium antimonide; surface reconstructions; bismuth deposition; scanning tunneling microscopy; X-ray photoelectron spectroscopy.; Physics and Astronomy;

   Sammanfattning : In recent years, III-V semiconductor materials have received increasing attention due to their admirable electronic properties like direct tunable bandgaps and high charge carrier mobility. Indium Antimonide (InSb) possesses the largest electron mobility among III-V materials and is promising for infrared detectors, high-speed field effect transistors, and spintronics. LÄS MER