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Infrastructure of Thin Films Division in IMP Hubert Głowiński and Janusz Dubowik, IFM PAN Outline VNA-FMR FMR PIMM Dynamic measurements VSM PPMS MOKE Static measurements GIXRD XRF Structural characterization Field sweep FMR • During field sweep FMR experiment magnetization vector changes its direction FMR Gaussmeter Microwave bridge Lock-in Field sweep controller • X-band spectrometer 9.18 GHz • Field up to 11 kOe VNA-FMR Port 1 Port 2 On frequency sweep FMR experiment magnetization vector does not change its direction Próbka Microwave field Coplanar waveguide External magnetic field • Frequency up to 40 GHz CPW – coplanar waveguide External magnetic field Magnetic field lines Electric field lines Simulated current Homogenous current I. Neudecker et al. JMMM 307 (2006) 148–156 Channelized Coplanar Waveguide The vias are acting as a microwave wall The other determining factor in the high frequency performance of the vias is the spacing between the rows of the vias. The wider the spacing, the lower the cutoff frequency and the closer the spacing the higher the cutoff frequency. http://mpd.southwestmicrowave.com/pdf/Launch_Report.pdf VNA-FMR Gaussmeter VNA Helmholtz’ s coils Power supply VNA-FMR Frequency sweep mode Different fields Field sweep mode Different frequencies 0,2313 0,2312 0,2311 Free 0,2310 Polarizer 0,2309 A [a.u.] 0,2308 0,2307 0,2306 0,2305 0,2304 20 GHz 0,2303 Analyzer 0,2302 0,2301 0,2300 0 2000 4000 6000 Field [Oe] 8000 10000 12000 Au Co Au Co Au Co Au Co Au Co Au Ti Si Pulsed inductive microwave magnetometer (PIMM) Pulse generator Trigger Port Port Sampling oscilloscope Pulse magnetic field Sample External magnetic field Bandwidth 20 GHz Pulse risetime 55 ps Pulse amplitude 10 V PIMM Pulse generator Oscilloscope Helmholtz coils Power supply Vibrating Sample Magnetometer – VSM • Frequency: 35 Hz • Dual pickup coils • Magnetic field: up to 16 kOe • Temperature: -100oC to 250oC M.Matczak, Thesis, Politechnika Poznańska, Poznań, 2011 Generator Gaussmeter Loudspeaker Glass pipe Hallo tron PC Power supply Pickup coils Lock-in PHYSICAL PROPERTY MEASUREMENT SYSTEM (PPMS) • Options – VSM – Resistance – Torque magnetometer • PPMS system properties: – Temperature range: 2 K 350 K. – Magnetic field: up to 9 tesla. – Magnetic field ramp rate: determined by magnet and power supply. – Temperature and magnetic field may be ramped during the measurement. MOKE Z axis Stepper motor Modulator Polarizer Lens Mirror Elektromagnet Laser Wavelength λ=640 nm Modulator Analyzer Gauss meter Lens Detector M.Matczak, Thesis, Politechnika Poznańska, Poznań, 2011 Power supply Lock-in PC MOKE – device setup 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. M.Matczak, Thesis, Politechnika Poznańska, Poznań, 2011 Laser diode Polarizer Modulator Lens Electromagnet Sample holder and table Mirror Analyser Lens Detector (fotodiode) Magnetic field sensor MOKE M [a.u.] Ti4/Au60/(Co0.8/Au1)3/Au2/Co1.5/Au2/Co3/Au5 40 20 0 -20 -40 -60 -80 -100 -120 -140 -160 -180 -200 -220 -240 -260 -280 -300 0 2 4 6 8 0 2 4 6 8 -8 -6 -4 -2 0 H [kOe] 2 4 6 8 Au Co Au Co Au Co Au Co Au Co Au Ti Si XRF Characteristic radiation Multichannel analyzer 10 keV / 1024 channels • We can measure: – Thickness of thin films (up to 200 nm) – Chemical elements composition K. Załęski, Masters thesis, UAM Wydział Fizyki, Poznań 2007 1 – X-ray source, 2 - collimator, 3 – sample holder, 4 - detector Wikipedia GIXRD Seifert, model XRD 3003, X-ray source Cu-K (wavelength λ=0.15419 nm) Interference of the wave reflected from surface of the film and the surface of the substrate results in Kiessiga fringes. Allows to measure thickness of thin films P. Kuświk, PhD dissertation, IFM PAN, Poznań, 2010 2θ varies 0o - 10o aperture X-ray source sample detector Summary • We are able to characterize magnetically samples (effective fields, anisotropy, damping parameter) • We are able to characterize structure of the sample (film thickness, sublayer thickness, chemical composition) Thank you for your attention!