o:20065
Experimental characterization of magneto-optical properties of Faraday crystal applied in magnetic field sensor
doctoral dissertation
Eksperimentalna karakterizacija magneto-optičkih osobina Faradejevog kristala namenjenog za konstrukciju senzora magnetskog polja : doctoral dissertation
en
The thesis explores preparation and magneto properties of bismuth
germanium oxide single crystal (B12GeO20) which is irradiated by pulsed
femtosecond laser of increasing power. Analyses performed on irradiated and
un irradiated samples showed significant changes in transmittance, transmission
spectra, sample color, Raman spectra (RS), X-ray diffraction (XRD) pattern,
Verdet constant (VC), magneto-optical property and absorption coefficient. After
irradiation, the transmission spectra values increased whereas anisotropy
detected in the transmission spectra of unirradiated samples disappeared. The
change of color caused by irradiation was noticeable to the naked eye. The XRD
measurements confirmed structural changes induced by laser irradiation, i.e., the
laser- beam-incident side of the sample became almost amorphous, whereas the
side opposite to the incident can be indexed to the Bi12 Ge O20 compound.
Irradiation caused increase of Raman spectra peaks with the exception of crystal
peaks of type E, which disappeared. The femtosecond pulsed laser irradiation
can be used to improve bismuth germanium oxide single crystal optical
properties. Femtosecond pulsed laser irradiation can improve optical properties
of Bi12 GeO20 single crystals.
Disertacija razmatra pripremu za proizvodnju i magneto optička
svojstva Bizmut germanijum oksidnih kristala (B12GeO20) koje se ozračuju
femtosekundnim laserskim impulsima zracima sa rastućom snagom. Analize
izvršene nad ozračenim i neozračenim uzorcima kristala pokazale su značajne
promene u transmitansi, transmisionom spektru, boji, Ramanovom spektru,
rezultatima difrakcije X zraka, Verdeovoj konstanti, magneto-optičkim
svojstvima i koeficijentu apsorpcije. Posle ozračivanja došlo je do porasta
transmitivnosti i izostanka anizotropije u transmisionom spektru u odnosu na
neozračene uzorke. Izmena boje uzoraka primetna je čak i golim okom. XRD
merenja pokazala su strukturne promene indukovane laserskim zracima tako da
je npr. strana uzorka neposredno ozračena laserom postala skoro potpuno
amorfna dok se suprotna strana uzorka indeksira na B12GeO20 jedinjenje.
Ozračivanje je izazvalo porast vrhova u Ramanovom spektru sa izuzetkom
vrhova za tip E koji se nisu pojavili. Femtosekundni laserski impulsi mogu se
iskoristiti da unaprede optička svojstva kristala...
Electrical Engineering - Optoelectronics / Elektrotehnika i računarstvo - Optoelektronika
Datum odbrane: 07.03.2019.
Faradejev kristal, senzor magnetskog polja, delta/sigmanormalizacija, temperaturska svojstva kristala
Faraday crystal, magnetic field sensor, delta/sigma normalization,crystal temperature properties
yes
51496719
91552101
6878
91552100
51496719
2019-09-16T15:40:10.053Z
45
no
46
mentor
Giuma Saleh Isa, 1963- 21611623
Abudagel
2019
63
mentor
Slobodan, 1971- 14775143
Petričević
2019
63
član komisije
Zlatan, 1960- 12559207
Stojković
2019
63
član komisije
Nebojša, 1963- 8769895
Romčević
2019
63
član komisije
Peđa, 1973- 25418599
Mihailović
2019
63
član komisije
Marko, 1978-15814247
Barjaktarević
2019
103 lista
1878782
http://phaidrabg.bg.ac.rs/o:20065
no
yes
3
2019-09-16T15:40:10.320Z
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Faraday crystal, magnetic field sensor, delta/sigma normalization,crystal temperature properties
Faradejev kristal, senzor magnetskog polja, delta/sigmanormalizacija, temperaturska svojstva kristala
1738
2019