From Materials to Neuromorphic Circuits

Our research spans the entire chain from material synthesis to device integration:

  1. Material Growth & Characterisation
    • Pulsed laser deposition of GCMO thin films
    • Structural, electrical, and magnetic measurements
  2. Device Fabrication
    • Patterning memristor structures
    • Contact engineering and encapsulation for stability
  3. Memristor Physics
    • Understanding switching mechanisms
    • Optimising endurance, retention, and power consumption
  4. Circuit & System Applications
    • Implementing GCMO devices in spiking neuron circuits
    • Hardware for proof-of-concept applications

Research output

Publications

  1. Antola, A; Laaksonen, J; Huhtinen, H.; Angervo, I; Granroth, S; Schulman, S; Laukkanen, P; Paturi,P  Area-Dependent Resistive Switching and Interfacial Dynamics in GCMO-Based Memristors ACS APPLIED ELECTRONIC MATERIALS  7, 4242-4250 (2025) doi.org/10.1021/acsaelm.5c00403
  2. Schulman, A; Huhtinen, H; Paturi, P Manganite memristive devices: recent progress and emerging opportunities, JOURNAL OF PHYSICS D-APPLIED PHYSICS 57, 422001 (2024) doi.org/10.1088/1361-6463/ad6575
  3. Angervo, I; Antola, A; Vaimala, T; Malmi, A; Schulman, A; Huhtinen, H; Paturi, P Importance of growth method and substrate-induced crystalline quality in Al/Gd2Ca0.8MnO3/Au memristor devices, JOURNAL OF PHYSICS D-APPLIED PHYSICS 57, 415301 (2024) doi.org/10.1088/1361-6463/ad6271
  4. Antola, A; Angervo, I; Huhtinen, H; Miettinen, M; Schulman, A; Paturi, P Structurally simplified GCMO crossbar design for artificial synaptic networks, APPLIED PHYSICS LETTERS 124, 253502 (2024) doi.org/10.1063/5.0210544
  5. Paasonen, VMM; Angervo, I; Antola, A; Huhtinen, H; Paturi, P Scalable and environmentally friendly production of perovskite manganite thin films for neuromorphic applications, THIN SOLID FILMS 798, 140381 (2024) doi.org/10.1016/j.tsf.2024.140381
  6. Angervo, I; Antola, A; Schulman, A; Huhtinen, H; Paturi, P The effect of substrate-induced defects on structural and resistive switching properties in Gd2Ca0.8MnO3 thin films, AIP ADVANCES 14, 45309 (2024) doi.org/10.1063/5.0185499
  7. Hynnä, T; Schulman, A; Lähteenlahti, V; Huhtinen, H; Paturi, P Bioplausible Synaptic Behavior of Al/Gd3Ca0.7MnO3/Au Memristive Devices for Unsupervised Spiking Neural Networks, ACS APPLIED ELECTRONIC MATERIALS 6, 292 (2023) doi.org/10.1021/acsaelm.3c01273
  8. Beiranvand, A; Liedke, MO; Haalisto, C; Lähteenlahti, ; Schulman, A; Granroth, S; Palonen, H; Butterling, M; Wagner, A; Huhtinen, H; Paturi, P Manipulating magnetic and magnetoresistive properties by oxygen vacancy complexes in GCMO thin films, JOURNAL OF PHYSICS-CONDENSED MATTER 34, 155804 (2022) doi.org/10.1088/1361-648X/ac4eac
  9. Miranda, E; Lahteenlahti, V; Huhtinen, H; Schulman, A; Paturi, P Compact Modeling and SPICE Simulation of GCMO-Based Resistive Switching Devices, IEEE TRANSACTIONS ON NANOTECHNOLOGY 21, 285 (2022) doi.org/10.1109/TNANO.2022.3181500
  10. Beiranvand, A; Rivasto, E; Huhtinen, H; Paturi, P Strain-Induced Domain Structure and Its Impact on Magnetic and Transport Properties of Gd6Ca0.4MnO3 Thin Films, ACS OMEGA 6, 34572 (2021) doi.org/10.1021/acsomega.1c04904
  11. Beiranvand, A; Liedke, MO; Haalisto, C; Lahteenlahti, V; Schulman, A; Granroth, S; Palonen, H; Butterling, M; Wagner, A; Huhtinen, H; Paturi, P Tuned AFM-FM coupling by the formation of vacancy complex in Gd6Ca0.4MnO3 thin film lattice, JOURNAL OF PHYSICS-CONDENSED MATTER 33, 255803 (2021) doi.org/10.1088/1361-648X/abf9ba
  12. Lähteenlahti, V; Schulman, A; Beiranvand, A; Huhtinen, H; Paturi, P Electron Doping Effect in the Resistive Switching Properties of Al/Gd1-xCaxMnO3/Au Memristor Devices, ACS APPLIED MATERIALS & INTERFACES 13, 18365 (2021) doi.org/10.1021/acsami.1c02963
  13. Acha, C; Sanca, GA; Barella, M; Alurralde, M; Marlasca, FG; Huhtinen, H; Paturi, P; Golmar, F; Levy, P Proton irradiation effects on metal-YBCO interfaces, RADIATION PHYSICS AND CHEMISTRY 183, 109404 (2021) doi.org/10.1016/j.radphyschem.2021.109404
  14. Schulman, A; Palonen, H; Lahteenlahti, V; Beiranvand, A; Huhtinen, H; Paturi, P Metastable ferromagnetic flux closure-type domains in strain relaxed Gd1Ca0.9MnO3 thin films, JOURNAL OF PHYSICS-CONDENSED MATTER 33, 35803 (2021) doi.org/10.1088/1361-648X/abbe7d
  15. Acha, C; Barella, M; Sanca, GA; Marlasca, FG; Huhtinen, H; Paturi, P; Levy, P; Golmar, F YBCO-based non-volatile ReRAM tested in Low Earth Orbit, JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS 31, 16389 (2020) doi.org/10.1007/s10854-020-04190-0
  16. Lanosa, LF; Huhtinen, H; Paturi, P; Acha, C Electrical conduction mechanisms of metal/high-Tc superconductor (YBCO) interfaces, JOURNAL OF PHYSICS-CONDENSED MATTER 32, 175001 (2020) doi.org/10.1088/1361-648X/ab6b8b
  17. Schulman, A; Beiranvand, A; Lähteenlahti, V; Huhtinen, H; Paturi, P Appearance of glassy ferromagnetic behavior in Gd1-xCaxMnO3 (0 ≤ x ≤ 1) thin films: A revised phase diagram, JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS 498, 166149 (2020) doi.org/10.1016/j.jmmm.2019.166149
  18. Lahteenlahti, V; Schulman, A; Huhtinen, H; Paturi, P Transport properties of resistive switching in Ag/Pr6Ca0.4MnO3/Al thin film structures, JOURNAL OF ALLOYS AND COMPOUNDS 786, 84 (2019) doi.org/10.1016/j.jallcom.2019.01.279
  19. Ben Hamed, H; Hoffmann, M; Adeagbo, WA; Ernst, A; Hergert, W; Hynninen, T; Kokko, K; Paturi, P First-principles investigations of the magnetic phase diagram of Gd1-xCaxMnO3, PHYSICAL REVIEW B 99, 144428 (2019) doi.org/10.1103/PhysRevB.99.144428
  20. Beiranvand, A; Tikkanen, J; Huhtinen, H; Paturi, P Metamagnetic transition and spin memory effect in epitaxial Gd1-xCaxMnO3 (0 ≤ x ≤ 1) thin films, JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS 469, 253 (2019) doi.org/10.1016/j.jmmm.2018.08.002
  21. Elovaara, T; Tikkanen, J; Granroth, S; Majumdar, S; Félix, R; Huhtinen, H; Paturi, P Mechanisms of photoinduced magnetization in Pr6Ca0.4MnO3 studied above and below charge-ordering transition temperature, JOURNAL OF PHYSICS-CONDENSED MATTER 29, 425802 (2017) doi.org/10.1088/1361-648X/aa847b
  22. Beiranvand, A; Tikkanen, J; Huhtinen, H; Paturi, P Electronic and magnetic phase diagram of polycrystalline Gd1-xCaxMnO3 manganites, JOURNAL OF ALLOYS AND COMPOUNDS 720, 126 (2017) doi.org/10.1016/j.jallcom.2017.05.231
  23. Tikkanen, J; Huhtinen, H; Paturi, P Dynamic mesoscale model of the metamagnetic transition in low-bandwidth perovskite manganites, PHYSICAL REVIEW B 96, 14405 (2017) doi.org/10.1103/PhysRevB.96.014405
  24. Paturi, P; Tikkanen, J; Huhtinen, H Room temperature charge-ordered phase in Gd6Ca0.4MnO3 and Sm0.6Ca0.4MnO3 thin films, JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS 432, 164 (2017) doi.org/10.1016/j.jmmm.2017.01.080
  25. Beiranvand, A; Tikkanen, J; Rautakoski, J; Huhtinen, H; Paturi, P Estimates of the magnetocaloric effect in (Nd, Ca)MnO3 and (Gd, Ca)MnO3 based on magnetic transition entropies, MATERIALS RESEARCH EXPRESS 4, 36101 (2017) doi.org/10.1088/2053-1591/aa5fc9
  26. Tikkanen, J; Geilhufe, M; Frontzek, M; Hergert, W; Ernst, A; Paturi, P; Udby, L The low-temperature magnetostructure and magnetic field response of Pr9Ca0.1MnO3: the roles of Pr spins and magnetic phase separation, JOURNAL OF PHYSICS-CONDENSED MATTER 28, 36001 (2016) doi.org/10.1088/0953-8984/28/3/036001
  27. Elovaara, T; Majumdar, S; Huhtinen, H; Paturi, P Photoinduced Colossal Magnetoresistance under Substantially Reduced Magnetic Field, ADVANCED FUNCTIONAL MATERIALS 25, 5030 (2015) doi.org/10.1002/adfm.201502233
  28. Tikkanen, J; Huhtinen, H; Paturi, P Oxygen-sintered (Pr, Ca) MnO3: Structure and magnetism at high Ca concentrations, JOURNAL OF ALLOYS AND COMPOUNDS 635, 41 (2015) doi.org/10.1016/j.jallcom.2015.02.098
  29. Elovaara, T; Ahlqvist, T; Majumdar, S; Huhtinen, H; Paturi, P Melting of the charge-ordered state under substantially lower magnetic field in structurally improved Pr1-xCaxMnO3 (x=0.3-0.5) thin films, JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS 381, 194 (2015) doi.org/10.1016/j.jmmm.2014.12.082
  30. Elovaara, T; Majumdar, S; Huhtinen, H; Paturi, P Defect induced enhanced low field magnetoresistance and photoresponse in Pr6Ca0.4MnO3 thin films, 20TH INTERNATIONAL CONFERENCE ON MAGNETISM, ICM 2015 75, 62 (2015) doi.org/10.1016/j.phpro.2015.12.010
  31. Tikkanen, J; Kauhala, S; Huhtinen, H; Paturi, P Anomalous Thermal Expansion in (Pr, Ca)MnO3 due to Orbital Ordering, 20TH INTERNATIONAL CONFERENCE ON MAGNETISM, ICM 2015 75, 475 (2015) doi.org/10.1016/j.phpro.2015.12.059
  32. Nyman, M; Elovaara, T; Tikkanen, J; Majumdar, S; Huhtinen, H; Paturi, P Epitaxially Textured Pr6Ca0.4MnO3 Thin Films Under Considerably Low Substrate Temperature, 20TH INTERNATIONAL CONFERENCE ON MAGNETISM, ICM 2015 75, 1122 (2015) doi.org/10.1016/j.phpro.2015.12.180
  33. Majumdar, S; Huhtinen, H; Elovaara, T; Paturi, P Stronger Photo-Induced Effect in Epitaxial Thin Films of Small-Bandwidth Manganite Pr1-xCaxMnO3 Compared to the Polycrystalline Bulk, JOURNAL OF SUPERCONDUCTIVITY AND NOVEL MAGNETISM 28, 197 (2015) doi.org/10.1007/s10948-014-2838-z
  34. Tikkanen, J; Huhtinen, H; Paturi, P The Magnetocaloric Performance of (Pr,Ca) Manganites Estimated by Magnetic Transition Entropies, IEEE TRANSACTIONS ON MAGNETICS 50, 2504004 (2014) doi.org/10.1109/TMAG.2014.2324656
  35. Elovaara, T; Huhtinen, H; Majumdar, S; Paturi, P Linear and nonlinear ac susceptibilities in polycrystalline low-bandwidth Pr1-xCaxMnO3(x=0.0-0.3) manganite, JOURNAL OF PHYSICS-CONDENSED MATTER 26, 266005 (2014) doi.org/10.1088/0953-8984/26/26/266005
  36. Elovaara, T; Huhtinen, H; Majumdar, S; Paturi, P Study of Dynamic Magnetism in Low Bandwidth Manganite PrCaMnO by Ac Susceptibility Measurements, JOURNAL OF LOW TEMPERATURE PHYSICS 175, 554 (2014) doi.org/10.1007/s10909-014-1108-6
  37. Majumdar, S; Huhtinen, H; Paturi, P Comparative Study of Persistent Photo-Induced Magnetization in Low and Intermediate Bandwidth Manganite Thin Films, JOURNAL OF SUPERCONDUCTIVITY AND NOVEL MAGNETISM 26, 1455 (2013) doi.org/10.1007/s10948-012-1970-x
  38. Majumdar, S; Elovaara, T; Huhtinen, H; Granroth, S; Paturi, P Crystal asymmetry and low-angle grain boundary governed persistent photoinduced magnetization in small bandwidth manganites, JOURNAL OF APPLIED PHYSICS 113, 63906 (2013) doi.org/10.1063/1.4789596
  39. Elovaara, T; Huhtinen, H; Majumdar, S; Paturi, P Irreversible metamagnetic transition and magnetic memory in small-bandwidth manganite Pr1-xCaxMnO3 (x=0.0-0.5), JOURNAL OF PHYSICS-CONDENSED MATTER 24, 216002 (2012) doi.org/10.1088/0953-8984/24/21/216002
  40. Majumdar, S; Huhtinen, H; Granroth, S; Paturi, P Evolution of structural and magnetic properties with varying oxygen content in low-bandwidth manganite Pr9Ca0.1MnO3 thin films, JOURNAL OF PHYSICS-CONDENSED MATTER 24, 206002 (2012) doi.org/10.1088/0953-8984/24/20/206002
  41. Majumdar, S; Huhtinen, H; Majumdar, HS; Paturi, P Stress and defect induced enhanced low field magnetoresistance and dielectric constant in La7Sr0.3MnO3 thin films, JOURNAL OF ALLOYS AND COMPOUNDS 512, 332 (2012) doi.org/10.1016/j.jallcom.2011.09.093
  42. Svedberg, M; Majumdar, S; Huhtinen, H; Paturi, P; Granroth, S Optimization of Pr9Ca0.1MnO3 thin films and observation of coexisting spin-glass and ferromagnetic phases at low temperature, JOURNAL OF PHYSICS-CONDENSED MATTER 23, 386005 (2011) doi.org/10.1088/0953-8984/23/38/386005

Theses

  1. Tomi Elovaara, Magnetophotoresistance in Pr1–xCaxMnO3 Thin Films (2016)
  2. Jussi Tikkanen,Praseodymium Calcium Manganites : Magnetism Across Length Scales (2017)
  3. Azar Beiranvand Low bandwidth manganite (Gd,Ca)MnO3 for future memristor devices (2022)
  4. Ville Lähteenlahti, Memristor devices based on low-bandwidth manganites (2022)

Patents

  1. Paturi, A. Schulman, H. Huhtinen, V. Lähteenlahti and A. Beiranvand, Novel thin film material for memristor, and a memristor comprising such material, (2020)
  2. Paturi, H. Huhtinen, V. Paasonen and I. Angervo, Aqueous solutions, methods of manu- facturing the same and uses thereof, (2022)
  3. Paturi, H. Huhtinen, A. Antola, I. Angervo and A. Schulman, Memristor array and method of manufacturing thereof,  (2023)
  4. Paturi, H. Huhtinen, A. Antola, I. Angervo, Memristor-based neuron, filed  6/2025.