Aleksandr
Kadykov

Research Engineer

Proven ability to design and execute experiments, analyse and present data, develop scientific Python software. Strong background in applied and basic research in THz photonics and solid-state physics.

Core competencies

  • Data analysis & presentation
  • Experimental design & execution
  • Instrumentation integration & orchestration
  • Scientific Python development

Professional experience

Multitel A.S.B.L.

Jul. 2021 — Aug. 2024

Non-profit innovation center based in Mons, Belgium with ~100 employees, specializing in applied photonics, IoT, AI, and railway certification.

Research Software Engineer in THz Spectroscopy and Imaging

  • Developed a THz time-domain spectroscopy (THz-TDS) data pipeline with an improved signal-to-noise ratio by utilizing sensitivity profile-shaped filtering.

  • Developed a computationally cheap THz-TDS data processing method for refractive index and thickness extraction in low-absorption materials.

  • Streamlined refractive index profile reconstruction from THz-TDS data by offloading calculations to a GPU and utilizing backpropagation-based optimization algorithms.

  • Implemented a low-cost operation and high spectral quality broadband THz-TDS setup by suppressing atmospheric absorption with silica gel-based dehumidification.

  • Automated laboratory workflows by implementing Python tools for measurement orchestration, data management, analysis, and result presentation.

  • Ensured best software development practices by implementing unit testing, CI/CD pipelines, and documentation.

  • Led the SAPHIRE project, developing non-destructive in-situ solutions to control pill coating thickness and humidity.

  • Led the development of THz-TDS-based methods for polymer wastes sorting.

Laboratoire National de Métrologie et d’Essais (LNE)

Sep. 2018 — Sep. 2020

French National Laboratory of Metrology and Testing, an EPIC company with ~1000 employees, Trappes, France.

Research Engineer in Quantum Hall Effect Metrology

  • Led low-noise cryogenic magnetotransport measurements on graphene, exploring its potential as a resistance standard.

  • Designed a flexible Python software package, optimizing scientific equipment orchestration.

  • Participated in the nanofabrication of hBN-encapsulated graphene stacks.

  • Improved performance of a helium gas recuperation system.

Institute for Physics of Microstructures RAS

May 2017 — Sep. 2018

State-owned research institute with ~200 employees based in Nizhny Novgorod, Russia

Research Engineer in Photonics of 2D Narrow-Gap Heterostructures

  • Led photoluminescence and photoconductivity FTIR cryogenic measurements of HgTe/HgCdTe quantum wells.

  • Achieved laser emission in HgCdTe heterostructures at a record wavelength.

Education

Laboratoire Charles Coulomb (L2C) | IPM RAS

Sep. 2014 — Dec. 2017

Montpellier, France | Nizhny Novgorod, Russia

Ph.D. in Physics

Physical properties of HgCdTe-based heterostructures: towards terahertz emission and detection

Other relevant information

Data analysis & presentation

Python, NumPy, Pandas, Xarray, SciPy, Matplotlib, hvPlot, Plotly, Bokeh, Panel, Intake,

Instrumentation integration & orchestration

PyMeasure, Bluesky, yaq, LabVIEW

Reporting

Quarto, Jupyter, Typst, LaTeX, RevealJS

Programming

VSCode, Git, Linux, Docker, PyTest, Pre-Commit, GitLab CI/CD, GitHub Actions, TDD, Devcontainers

Languages

Selected publications

  1. Kadykov, A.M., Torres, J., Krishtopenko, S.S. et al., Terahertz imaging of Landau levels in HgTe-based topological insulators, Applied Physics Letters, 108(26), 262102, 2016
  2. Teppe, F., Marcinkiewicz, M., Krishtopenko, S.S. et al., Temperature-driven massless Kane fermions in HgCdTe crystals, Nature Communications, 7, 12576, 2016
  3. Kadykov, A.M., Krishtopenko, S.S., Jouault, B. et al., Temperature-Induced Topological Phase Transition in HgTe Quantum Wells, Physical Review Letters, 120(8), 086401, 2018
  4. Kadykov, A.M., Teppe, F., Consejo, C. et al., Terahertz detection of magnetic field-driven topological phase transition in HgTe-based transistors, Applied Physics Letters, 107(15), 152101, 2015
  5. Krishtopenko, S.S., Ruffenach, S., Gonzalez-Posada, F. et al., Temperature-dependent terahertz spectroscopy of inverted-band three-layer InAs / GaSb / InAs quantum well, Physical Review B, 97(24), 245419, 2018
  6. Ruffenach, S., Kadykov, A.M., Rumyantsev, V.V. et al., HgCdTe-based heterostructures for terahertz photonics, APL Materials, 5(3), 035503, 2017
  7. Yahniuk, I., Krishtopenko, S.S., Grabecki, G. et al., Magneto-transport in inverted HgTe quantum wells, npj Quantum Materials, 4(1), 1—8, 2019
  8. Marcinkiewicz, M., Ruffenach, S., Krishtopenko, S.S. et al., Temperature-driven single-valley Dirac fermions in HgTe quantum wells, Physical Review B, 96(3), 035405, 2017
  9. Morozov, S.V., Rumyantsev, V.V., Fadeev, M. et al., Stimulated emission from HgCdTe quantum well heterostructures at wavelengths up to 19.5~um, Applied Physics Letters, 111(19), 192101, 2017
  10. Morozov, S.V., Rumyantsev, V.V., Kadykov, A.M. et al., Long wavelength stimulated emission up to 9.5~um from HgCdTe quantum well heterostructures, Applied Physics Letters, 108(9), 092104, 2016
  11. Morozov, S.V., Rumyantsev, V.V., Dubinov, A.A. et al., Long wavelength superluminescence from narrow gap HgCdTe epilayer at 100~K, Applied Physics Letters, 107(4), 042105, 2015
  12. Morozov, S.V., Rumyantsev, V.V., Antonov, A. et al., Time resolved photoluminescence spectroscopy of narrow gap Hg1-xCdxTe/CdyHg1-yTe quantum well heterostructures, Applied Physics Letters, 105(2), 022102, 2014
  13. Rumyantsev, V.V., Kozlov, D.V., Morozov, S.V. et al., Terahertz photoconductivity of double acceptors in narrow gap HgCdTe epitaxial films grown by molecular beam epitaxy on GaAs(013) and Si(013) substrates, Semiconductor Science and Technology, 32(9), 095007, 2017
  14. Fadeev, M.A., Rumyantsev, V.V., Kadykov, A.M. et al., Stimulated emission in the 2.8—3.5~um wavelength range from Peltier cooled HgTe/CdHgTe quantum well heterostructures, Optics Express, 26(10), 12755, 2018
  15. Kadykov, A.M., Consejo, C., Marcinkiewicz, M. et al., Observation of topological phase transition by terahertz photoconductivity in HgTe-based transistors, physica status solidi (c), 13(7), 534—537, 2016
  16. Kadykov, A.M., Consejo, C., Teppe, F. et al., Terahertz excitations in HgTe-based field effect transistors, Journal of Physics: Conference Series, 647(1), 012009, 2015
  17. Bovkun, L.S., Krishtopenko, S.S., Ikonnikov, A.V. et al., Magnetospectroscopy of double HgTe/CdHgTe quantum wells, Semiconductors, 50(11), 1532—1538, 2016
  18. Aleshkin, V.Y., Gavrilenko, L.V., Gaponova, D.M. et al., Nonresonant radiative exciton transfer by near field between quantum wells, Journal of Experimental and Theoretical Physics, 117(5), 944—949, 2013
  19. Morozov, S.V., Rumyantsev, V.V., Kadykov, A.M. et al., Investigation of possibility of VLWIR lasing in HgCdTe based heterostructures, Journal of Physics: Conference Series, 647(1), 012008, 2015
  20. Kozlov, D.V., Rumyantsev, V.V., Morozov, S.V. et al., Impurity-induced photoconductivity of narrow-gap Cadmium—Mercury—Telluride structures, Semiconductors, 49(12), 1605—1610, 2015
  21. Rumyantsev, V.V., Fadeev, M.A., Morozov, S.V. et al., Long-wavelength stimulated emission and carrier lifetimes in HgCdTe-based waveguide structures with quantum wells, Semiconductors, 50(12), 1651—1656, 2016
  22. Ikonnikov, A.V., Bovkun, L.S., Rumyantsev, V.V. et al., On the band spectrum in p-type HgTe/CdHgTe heterostructures and its transformation under temperature variation, Semiconductors, 51(12), 1531—1536, 2017
  23. Rumyantsev, V.V., Kadykov, A.M., Fadeev, M.A. et al., Investigation of HgCdTe waveguide structures with quantum wells for long-wavelength stimulated emission, Semiconductors, 51(12), 1557—1561, 2017
  24. Krishtopenko, S.S., Ikonnikov, A.V., Maremyanin, K.V. et al., Cyclotron resonance of Dirac fermions in InAs/GaSb/InAs quantum wells, Semiconductors, 51(1), 38—42, 2017
  25. Kozlov, D.V., Rumyantsev, V.V., Morozov, S.V. et al., Mercury vacancies as divalent acceptors in Hg1-xCdxTe/CdyHg1-yTe structures with quantum wells, Semiconductors, 50(12), 1662—1668, 2016
  26. Rumyantsev, V.V., Bovkun, L., Kadykov, A.M. et al., Magnetooptical Studies and Stimulated Emission in Narrow Gap HgTe/CdHgTe Structures in the Very Long Wavelength Infrared Range, Semiconductors, 52(4), 2018
  27. Kadykov, A.M., Teppe, F., Consejo, C. et al., Terahertz excitations in HgTe-based field effect transistors, 113—114, 2015
  28. Gavrilenko, V.I., Morozov, S.V., Rumyantsev, V.V. et al., THz lasers based on narrow-gap semiconductors, 1—4, 2016
  29. Marcinkiewicz, M., Krishtopenko, S.S., Ruffenach, S. et al., THz magnetospectroscopy of double HgTe quantum well, 1—2, 2016
  30. Morozov, S.V., Rumyantsev, V.V., Kadykov, A.M. et al., Long-wavelength stimulated emission in HgCdTe quantum well waveguide heterostructures, 2016-Novem, 1—2, 2016
  31. But, D.B., Consejo, C., Krishtopenko, S.S. et al., Terahertz cyclotron emission from HgCdTe bulk films, 2016-Novem, 1—2, 2016
  32. Yahniuk, I., Krishtopenko, S.S., Grabecki, G. et al., Graphene-like band structure (Hg, Cd) Te Quantum Wells for Quantum Hall Effect Metrology Applications, 229, 2017