Doctoral Candidate and Postdoc Positions on Magnonic/Plasmonic Devices, Magnonic Neural Networks, and Plasmonic Condensates/Nanolasers

Aalto University

Finland

February 28, 2022

Description

We are looking for highly motivated doctoral candidates and postdoctoral researchers to work on experiments in three projects: 1) optical control of spin waves for low-power computing, 2) YIG-based magnonic neural networks, and 3) plasmonic nanolasers and Bose-Einstein condensates (BEC) in flat and/or topological bands.

Project 1

This is a collaborative research project between the Nanomagnetism and Spintronics (NanoSpin) group (Prof. Sebastiaan van Dijken) and the Quantum Dynamics (QD) group (Prof. Päivi Törmä) at the Department of Applied Physics at Aalto University in Finland. The project aims at the excitation, manipulation, and detection of spin-wave signals in magnonic devices using ultrafast localized optical fields. The ultimate goal of the project is the realization of optically controlled magnonic logic gates. As a researcher, you will be working in a multidisciplinary team utilizing state-of-the-art facilities for materials growth, nanofabrication, and ultrafast spin-wave and optical characterization. The integrated magnonic/plasmonic devices consist of low-loss YIG-based magnonic waveguides with plasmonic nanodots patterned on top. A new time-resolved magneto-optical Kerr effect microscope will be developed to directly image the effects of nanoscale optical fields on propagating spin waves. The plasmonic structures will be designed using state- of-the-art modeling and theory available in the groups and characterized in our optics laboratory which provides real space and Fourier spectrally resolved imaging and ultrafast measurements. The NanoSpin group and QD group have collaborated successfully for eight years already, see for instance our new results on magnetic switching of plasmonic lasing in Nature Photonics ( Magnetic on–off switching of a plasmonic laser Nature Photonics ).

The project is funded for three years by two Finnish research foundations. We are looking for qualified candidates to fill two researcher positions with complementary profiles. Each position may be filled by a doctoral candidate or a postdoctoral researcher. A strong background in magnetism, magnonics, plasmonics, nanophotonics, or optics is required.

Project 2

This project aims at the experimental realization of magnonic neural networks and is conducted in the NanoSpin group of Prof. Sebastiaan van Dijken. As building blocks of the neural networks, patterned YIG films or YIG-based Fabry-Pérot resonators will be utilized as non-linear spin-wave scatterers. The neural networks will be designed and optimized using micromagnetic simulations and machine learning algorithms. Fabrication involves the growth of ultralow damping YIG films by pulsed laser deposition and advanced e-beam and direct laser-write lithography. Characterization of spin-wave transport along nanochannels will be conducted by broadband spin-wave spectroscopy and state-of-the-art time-resolved magneto-optical Kerr effect microscopy. One position is available within this project. We seek qualified and highly self-motivated applicants with solid training and proven experience in experimental techniques and nanofabrication with knowledge in magnetism, magnonics, and fluency in programming languages and data analysis.

Project 3

This is a project done mainly in the QD group of Prof. Päivi Törmä. It builds on our observation of a plasmonic BEC (see Bose–Einstein condensation in a plasmonic lattice Nature Physics and Phys. Rev. Lett. 127, 255301 (2021) - Spatial and Temporal Coherence in Strongly Coupled Plasmonic Bose-Einstein Condensates (aps.org) ) and lasing in nanoparticle arrays. This project explores these concepts in new types of nanoarrays, such as those hosting flat and/or topological bands. Lasing and BEC phenomena may show unique correlations and topologically protected quantities in such situations. In the project, suitable lattice geometries will be designed, and the lasing/BEC they host will be characterized with respect to spectral, coherence, correlation, and topological properties. The experiments will be supported by strong theory in the group, where we utilize our pioneering expertise on quantum geometry and superfluidity (see Superfluidity in topologically nontrivial flat bands Nature Communications and Phys. Rev. Lett. 127, 170404 (2021) - Quantum Geometry and Flat Band Bose-Einstein Condensation (aps.org)). In experiments, we have recently observed a quasi-BIC mode with a topological charge (Quasi-BIC Mode Lasing in a Quadrumer Plasmonic Lattice ACS Photonics), and collaboration with the NanoSpin group (Magnetic on–off switching of a plasmonic laser Nature Photonics ) provides an opportunity to create topological systems utilizing magnetic materials. One position is available within this project, for an experimentalist with expertise on plasmonics, polariton/photon condensates, (topological) photonics, or (quantum) optics.

REQUIREMENTS

We are looking for a bright and motivated postdocs or doctoral candidates with an excellent record in the fields of the positions. Good command of English (both verbal and written) and demonstrated ability to disseminate scientific results are mandatory requirements for the position. Applicants must be motivated to conduct research at the highest international level with the aim at publishing high-impact articles.

To be eligible for the doctoral candidate position, the candidate must have a M.Sc. or equivalent degree completed before the start of the employment. Postdoctoral researchers must hold a PhD degree in a suitable field.

SALARY AND WORKING TIME

Aalto University follows the salary system of Finnish universities. The salary ranges for a postdoc from 3700€ to 4100€ per month, depending on previous experience, and the postdoc contracts will initially be made for 2 years. Starting salary of a doctoral candidate is 2560€ per month and it increases as you progress in your research and studies. Following the standard practice in the Department of Applied Physics, the doctoral candidate contract will be made initially for two years, then extended to another two years after a successful mid-term progress review. The total duration of a PhD project is 4 years.

The annual workload of research and teaching staff at Aalto University is currently 1612 hours and the primary workplace will be the Otaniemi Campus at Aalto University . The contract includes Aalto University occupational healthcare.

PLACE AND INFRASTRUCTURE

You will join the NanoSpin group or the QD group at Aalto University. In project 1) you will be strongly affiliated with both groups, while projects 2) and 3) are mostly conducted by the NanoSpin and QD group, respectively. The NanoSpin group focuses on cutting-edge research on electric-field controlled magnetism, magnonics, and magneto-plasmonics in hybrid nanoscale structures. The NanoSpin laboratory is equipped with instrumentation for thin- film growth (magnetron sputtering and pulsed laser deposition), and several tools for advanced spin-wave characterization, including broadband spin-wave spectrometers and a time-resolved magneto-optical Kerr effect microscope. The QD group explores condensation and lasing phenomena as well as light-matter interactions in the nanoscale and combines experiments with quantum many-body theory research. The QD lab has a femtosecond laser and various fully automated optical characterization setups suited for studies of photonic nanostructures and lasing/condensation dynamics, including first and second order optical coherence measurements in the ultrafast scale. Besides, you will have full access to the OtaNano research infrastructure for nano- and microtechnologies, comprising state-of-the-art equipment for nanofabrication and microscopy. As a researcher in these two groups, you will be part of a vibrant and multidisciplinary research community. The projects involve national and international collaborations. For recent research output of the groups, please see ‪Sebastiaan van Dijken‬ - ‪Google Scholar‬ and ‪Päivi Törmä‬ - ‪Google Scholar‬.

Aalto University has six schools with nearly 11 000 students and 400 professors. It is the largest university in Finland focusing on education and research and technology, science, business, and arts. The two groups are located on the Otaniemi campus in Espoo (10 km from the city center of Helsinki), which is one of the largest hubs of high-tech in Northern Europe.

HOW TO APPLY

To apply for the position, please submit your application including the attachments mentioned below as one single PDF document in English through our online recruitment system by using the link on Aalto University's web page ("Apply Now”).

(1) Letter of motivation. Please specify whether you apply to project 1), 2), 3) or multiple projects.

(2) CV including list of publications

(3) Degree certificates and academic transcripts

(4) Contact details of at least two referees (or letters of recommendation, if already available)

The deadline for applications is 28 February 2022, but the position will remain open until filled. For additional information, kindly contact Prof. Sebastiaan van Dijken (sebastiaan.van.dijken@aalto.fi) and/or Prof. Päivi Törmä (paivi.torma@aalto.fi). Aalto University reserves the right for justified reasons to leave the position open, to extend the application period, reopen the application process, and to consider candidates who have not submitted applications during the application period.

Please note: Aalto University's employees and visitors should apply for the position via our internal system Workday -> find jobs (not external aalto.fi webpage on open positions) by using their existing Workday user account

ABOUT FINLAND

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