M.Sc Thesis

M.Sc StudentMasis Sergei
SubjectDiamond Magnetometry for Low-Temperature Applications
DepartmentDepartment of Nanoscience and Nanotechnology
Supervisor ASSOCIATE PROF. Eyal Buks
Full Thesis textFull thesis text - English Version


Optical detection of magnetic resonances of nitrogen-vacancy (NV) defects in a diamond lattice via a fiber bundle is applied to measure the Meissner shielding magnetic fields in a thin film type II superconductor at 4K. The electronic spin 1 structure of the NV center is sensitive to magnetic field, temperature, and strain. The spin state may be polarized with laser excitation, altered by standard electron spin resonance protocols and optically measured, as the photoluminescence of the center

depends on the spin state. The long coherence and relaxation times make the NV center rather a sensitive sensor. In this work, an NV magnetometer was designed, constructed and tested on a superconducting sample at 4K, without a noticeable impact on the sample temperature. The experimental results are compared with theoretical predictions based on the macroscopic critical state model with an acceptable agreement. Reducing the operation temperature by an order of magnitude

may allow quantum computation applications. The second topic of this thesis is design and fabrication of superconducting integrated circuits, that allow to engineer quantum Hamiltonians with macroscopic degrees of freedom like capacitance or inductance, compactly describing the joint dynamics of an Avogadro number of electrons. Basic building blocks of a quantum circuit, including a superconducting microwave resonator, coupled to a superconducting loop with a Josephson junction

were prepared and measured towards the integration with NV magnetometry.