Ämneskategori: Supraledning

Hittade 16 dokument

1. Lågpassfilter för supreledande mikrovågsresonatorer
   EDENBORG, PHILIP; LINA, HULTQUIST; MATTIAS, SJÖSTEDT; JOHAN, WINTHER
   Examensarbete för kandidatexamen, 2017 (Kandidatarbete)
   Vi hypotiserar att kommersiella bandpassfilter släpper igenom fotoner över supraledande aluminiums bandgapsfrekvens 88 GHz som orsakar förluster i supraledande mikrovågsresonatorer. Vi tillverkade distribueradelågpassfilter för att öka interna kvalitetsfaktorn Qiför resonatorerna. Filtrens frilagda ledare var av varierande längd och omgavs av Stycast. Mätnin...
2. Characterisation and optimisation of superconducting microwave resonators
   Boehme, Thijs
   Examensarbete på avancerad nivå, 2016 (MSc - Nanotechnology)
   In this master's thesis, I present the design, fabrication, and characterisation of superconducting microwave resonators. These resonators are quarter-wavelength coplanar waveguide resonators, operating at resonance frequencies between 4 GHz and 8 GHz. This kind of resonator is a key component in several applications, ranging from quantum computation devices...
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3. Parametric frequency conversion in two coupled superconducting resonators
   Bengtsson, Andreas
   Examensarbete på avancerad nivå, 2015 (MSc - Nanotechnology)
   In this work, we have designed, fabricated, and characterized two coupled superconducting microwave resonators.Using this system, we investigate a parametric frequency conversion process in the microwave regime. We modulate the resonance frequency at the difference frequency between two modes, i.e. by three-wave mixing. An incoming signal, resonant with one...
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4. Fabrication and Characterisation of Thin-Film Superconducting Nanowire Superinductors for Novel Quantum Devices
   Niepce, David
   Examensarbete på avancerad nivå, 2014 (MSc - Nanotechnology)
   In this master's thesis, we present the design, fabrication and characterisation of superconducting thin-film nanowire superinductances for use in quantum information processing and quantum metrology. In order to characterise the superconducting nanowire, it is placed inside a step-impedance lambda/2 microwave resonator.In a step-impedance resonator, the str...
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5. Thermal boundary resistance in YBCO THz microbolometers at room temperature
   Herman, Pierre
   Examensarbete på avancerad nivå, 2014 (MSc - Nanotechnology)
   Terahertz waves are utilized for a wide range of applications, from security, medical imaging to gas spectroscopy, etc. Previous investigations in the Teraherzt and Millimeter wave group at Chalmers, has shown that antenna-integrated Y Ba2Cu3O7 (YBCO) bolometer could serve as a potential detector for this range of the electromagnetic spectrum. The detector i...
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6. Holographic Superconductivity
   Wenger, Tobias
   Examensarbete på avancerad nivå, 2012 (MSc - Fundamental Physics)
   In this thesis we apply the AdS/CFT conjecture to condensed matter physics and more specifically we consider the application to layered superconductors. In this thesis we apply the AdS/CFT conjecture to condensed matter physics and more specifically we consider the application to layered superconductors. We start by analysing the "ordinary" 2+1 dimensional h...
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7. Photon generation in a doubly tunable resonator
   Svensson, Ida-Maria
   Examensarbete på avancerad nivå, 2012 (Civilingenjör)
   In November 2011 the first experimental observation of the dynamical Casimir effect waspublished [1]. Superconducting circuits were used to show that a single mirror movingin vacuum could generate photons, by parametric amplification of vacuum uctuations.This project is a side track of this research where a second mirror is introduced to investigatephoton ge...
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8. Paint it Black – To Protect the Qubits
   Fredriksson, Mattias; Svensson, Simon; Holmgren, Henning
   Examensarbete på grundnivå, 2012 (Högskoleingenjör)
   This thesis deals with reducing quasiparticle generation in superconducting circuits caused by stray photons by utilizing electromagnetic absorbers. This thesis deals with reducing quasiparticle generation in superconducting circuits caused by stray photons by utilizing electromagnetic absorbers. Quasiparticle generation is a known problem in several superco...
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9. Ultra-low field Magnetic Resonance Imaging using high-Tc SQUIDs
   Jönsson, Magnus
   Examensarbete på avancerad nivå, 2012 (Civilingenjör)
   A measurement system for ultra-low field Magnetic Resonance Imaging (ulf-MRI) has been built and programmed and a few proof-of- principle 2D images of water phantoms have been acquired at 89.3 μT measurement field. The smallest detectable volume of water has been de- termined to be 0.3 cm3. A single-shot NMR spectrum of a water sample has been detected and t...
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10. Tunneling into a Heavy Fermion System
    Spånslätt, Christian
    Examensarbete på avancerad nivå, 2012 (Civilingenjör)
    The discovery of an extremely high effective electron mass in CeAl3 by Andres et al in 1975 was the starting point for Heavy Fermion physics. One possible theory for explaining this heavy fermion behaviour is the Kondo lattice model which is investigated in this master thesis. With a slave boson mean field approach using Green’s functions, a set of mean fiel...
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11. Fabrication of air-bridges for qubit design
    Abuwasib, Mohammad
    Examensarbete på avancerad nivå, 2011 (Masterarbete)
    Superconducting quantum electrical circuit based on Co-planar waveguide technology is considered one of the most promising candidates for practical realization of aquantum computer in future. For purpose of designing a multi-qubit quantum processor which is the heart of a quantum computer, it is required to couple qubits to a large number of superconducting...
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12. Investigation of YBCO bolometers for THz wave detection
    Hammar, Arvid
    Examensarbete på avancerad nivå, 2011 (Masterarbete)
    The work presented in this master thesis is about the fabrication and char- acterization of bolometers based on thin films of YBa2Cu3O7−δ dedicated for detection of radiation in the THz-regime. A cleanroom process was developed to fabricate antenna-integrated bolometers on Al2O3 substrates. This process is described in detail to enable reproduction of the re...
13. Circuit Theory of Mesoscopic Superconducting Components
    Kellett, Ian
    Examensarbete på avancerad nivå, 2011 (Masterarbete)
    Nazarov's quantum circuit theory is essentially a discretised version of the Usadel equation which describes mesoscopic superconducting systems in the diffusive limit.The focus of this thesis project was to investigate the application of the quantum circuit theory to an Andreev interferometer.The report begins with a review of classical transport theory and...
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14. Investigation of Transmon Qubit Designs - A Study of Plasma Frequency Predictability
    Krantz, Philip
    Examensarbete på avancerad nivå, 2010 (MSc - Nanotechnology)
    This master thesis was dedicated to design, fabricate, and characterize subsystems of superconducting transmon qubits. Especially, focus was on investigating the predictability of the plasma frequency of the transmon, from which its operational properties are govern. In turn, the plasma frequency is governed by the normal state resistance of the two Josephso...
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15. Reading out a qubit through an harmonic oscillator, Simulating the driven Jaynes-Cummings Hamiltonian with dissipation
    Tornberg, Lars
    Examensarbete på avancerad nivå, 2005 (Civilingenjör)
    In this thesis we investigate the properties of a circuit proposed for reading out the state of a superconducting Cooper-pairbox (SCB). The circuit consists of an LC-circuit capacatively coupledto the SCB. By probing the LC-circuit the state of the qubit can bedetermined. The Hamiltonian for the circuit is derived and found to be thewell-known Jaynes-Cumming...
16. Feasibility study of HTS flux qubit read-out using aluminium dc-SQUID
    Johansson, Jesper
    Examensarbete på avancerad nivå, 2003 (Civilingenjör)
    This thesis for the degree of Master of Science studies and tests the feasibility of HTS flux qubit read-out using an aluminium dc-SQUID. The feasibility is studied on a device consisting of an YBCO dc-SQUID surrounded by an aluminium dc-SQUID separated by an intermediate layer. The intermediate layer acts as insulator between the YBCO and the aluminium and...
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