TRIUMF Canada's National Laboratory for Particle and Nuclear Physics STUDENT JOB PROGRAM Summer 2020 job posting Job number TR20-2-5 | ||
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Position Title:Spin Manipulation for Investigations of Magnetic Heterostructures | ||
Name of Project:Broadband Radiofrequency Techniques and Adiabatic Spin Rotation | ||
Overview:The Advanced Rare Isotope Laboratory (ARIEL), currently being constructed, will expand the scientific capabilities of the rare isotope program at TRIUMF by eventually tripling the amount of beamtime available for experiments and providing more exotic isotope species with high intensity. To make full use of ARIEL, an expansion of the nuclear spin-polarized beams facility in ISAC-1 is proposed. In particular, within materials science, a new spectrometer will be optimised for the next generation of depth resolved beta-NMR investigations of solid state heterostructures.Beta detected nuclear magnetic resonance or beta-NMR relies on the anisotropic emission of beta particles from the decay of spin polarized nuclei. The spin polarisation is high (~70%), compared to conventional nuclear magnetic resonance (NMR), as it does not rely on the differential occupation of energy levels of probe nuclei in thermal equilibrium. Sensitivity is greatly enhanced (10 orders of magnitude) and the required sample volume greatly reduced compared to conventional NMR. The current beta-NMR/beta-NQR spectrometers in ISAC-1 constitute a unique research tool, enabling spin polarised ions (typically 8Li+) to be controllably implanted at a depth of between 5 – 200 nm within a material for investigations of thin films and artificial heterostructures. There are two main goals proposed for this co-op term project: 1) the spins of the incident polarised radioactive nuclei must be capable of being manipulated, such that the artificial heterostructures may be investigated as a function of angle. The successful candidate will model the adiabatic rotation of these spins in an applied magnetic field, a fundamentally quantum mechanical problem. This modelling will guide the future design of the proposed beta-NMR spectrometer. 2) the controlled manipulation of a nonequilibrium spin population is a means of data storage or transfer, where for example, spin-up and spin-down states may be mapped onto bits 0 and 1. Generating a spin current (in the absence of the charge current typically used in today’s computers) for data transfer through spin pumping relies on the precession of the magnetisation induced in a ferromagnet excited by a radiofrequency magnetic field on resonance (FMR). The successful candidate will design and optimise a broadband air stripline for FMR measurements of artificial heterostructures. An existing prototype stripline will be used to undertake benchmark FMR investigations of a classic artificial heterostructure used for microwave applications based on Y3Fe5O12. | ||
Duties:The project will involve the design of a stripline for applying broadband radiofrequency (RF) magnetic fields to a sample of interest. The adiabatic response of a spin population to changing magnetic fields will also be modelled theoretically. | ||
Skills learned during this work experience:The successful candidate will gain a background in radiofrequency techniques, modelling and instrumentation. They will also be introduced to the use of ferromagnetic resonance techniques for characterisation of magnetic heterostructures. Finally, they will gain familiarity with calculating the quantum mechanical response of spins in an varying magnetic field. | ||
Qualifications:A third or fourth year undergraduate student in physics or engineering is sought. An aptitude and interest in the design, modelling, mechanical assembly and testing of broadband spin resonance probes is required. | ||
Shiftwork required:No | ||
Period of work:May - August 2020 with possible 4-month extension | ||
Salary is commensurate with academic progress and previous relevant work experience, and
ranges from $ 2080 to $ 2800 per month plus 4% vacation pay. TRIUMF pays round-trip airfare (this does not apply to Vancouver/Victoria students); for Vancouver Island students, TRIUMF will pay ferry costs.
TRIUMF is an equal opportunity employer committed to diversity in the workplace, and we
welcome applications from all qualified undergraduate students as defined below:
Applications must be received at TRIUMF by 4:00pm Pacific time on 2020-01-26. To apply for any of the job postings, you must submit one application for each and every job for which you wish to be considered. Please combine all documents into one PDF for each job. All applications can be attached to one email in PDF format. Please do not send electronic documents in formats other than PDF. Please save the PDF as lastname-job number (eg Smith-15.pdf)
Students within an university co-op program MUST apply for TRIUMF jobs through their university co-op education office.
No phone calls please. TRIUMF wishes to thank all applicants for their interest, and regrets that only those being considered will be contacted.
For more information, visit our web site http://www.triumf.ca |