0000000000927598
AUTHOR
Reinis Lazda
showing 7 related works from this author
Dynamic $^{14}\rm N$ nuclear spin polarization in nitrogen-vacancy centers in diamond
2020
We studied the dynamic nuclear spin polarization of nitrogen in negatively charged nitrogen-vacancy (NV) centers in diamond both experimentally and theoretically over a wide range of magnetic fields from 0 to 1100 G covering both the excited-state level anti-crossing and the ground-state level anti-crossing magnetic field regions. Special attention was paid to the less studied ground-state level anti-crossing region. The nuclear spin polarization was inferred from measurements of the optically detected magnetic resonance signal. These measurements show that a very large (up to $96 \pm 2\%$) nuclear spin polarization of nitrogen can be achieved over a very broad range of magnetic field start…
Hyperfine level structure in nitrogen-vacancy centers near the ground-state level anticrossing
2019
Energy levels of nitrogen-vacancy centers in diamond were investigated using optically detected magnetic-resonance spectroscopy near the electronic ground-state level anticrossing (GSLAC) at an axial magnetic field around 102.4~mT in diamond samples with a nitrogen concentration of 1~ppm and 200~ppm. By applying radiowaves in the frequency ranges from 0 to 40 MHz and from 5.6 to 5.9 GHz, we observed transitions that involve energy levels mixed by the hyperfine interaction. We developed a theoretical model that describes the level mixing, transition energies, and transition strengths between the ground-state sublevels, including the coupling to the nuclear spin of the NV center\textquotesing…
Dynamic N14 nuclear spin polarization in nitrogen-vacancy centers in diamond
2020
We studied the dynamic nuclear spin polarization of nitrogen in negatively charged nitrogen-vacancy (NV) centers in diamond both experimentally and theoretically over a wide range of magnetic fields from 0--1100 G covering both the excited-state level anticrossing and the ground-state level anticrossing magnetic field regions. Special attention was paid to the less studied ground-state level anticrossing region. The nuclear spin polarization was inferred from measurements of the optically detected magnetic resonance signal. These measurements show that a very large (up to $96\ifmmode\pm\else\textpm\fi{}2%$) nuclear spin polarization of nitrogen can be achieved over a very broad range of mag…
Level anti-crossing magnetometry with color centers in diamond
2017
Recent developments in magnetic field sensing with negatively charged nitrogen-vacancy centers (NV) in diamond employ magnetic-field (MF) dependent features in the photoluminescence (PL) and eliminate the need for microwaves (MW). Here, we study two approaches towards improving the magnetometric sensitivity using the ground-state level anti-crossing (GSLAC) feature of the NV center at a background MF of 102.4\,mT. Following the first approach, we investigate the feature parameters for precise alignment in a dilute diamond sample; the second approach extends the sensing protocol into absorption via detection of the GSLAC in the diamond transmission of a 1042\,nm laser beam. This leads to an …
Cross-relaxation studies with optically detected magnetic resonances in nitrogen-vacancy centers in diamond in an external magnetic field
2020
In this paper cross-relaxation between nitrogen-vacancy (NV) centers and substitutional nitrogen in a diamond crystal was studied. It was demonstrated that optically detected magnetic resonance signals (ODMR) can be used to measure these signals successfully. The ODMR were detected at axial magnetic field values around 51.2~mT in a diamond sample with a relatively high (200~ppm) nitrogen concentration. We observed transitions that involve magnetic sublevels that are split by the hyperfine interaction. Microwaves in the frequency ranges from 1.3 GHz to 1.6 GHz ($m_S=0\longrightarrow m_S=-1$ NV transitions) and from 4.1 to 4.6 GHz ($m_S=0\longrightarrow m_S=+1$ NV transitions) were used. To u…
Dimanta slāpekļa - vakanču optiskajos centros optiski reģistrējamo magnētisko rezonanšu modelēšana
2014
Maģistra darbā veikta optiski reģistrējamo magnētisko rezonanšu modelēšana ar 13C atomiem bagātinātu dimanta kristālu slāpekļa - vakanču (NV-) optiskajos centros. NV- centriem tiešā tuvumā esošo 13C atomu kodolu spini sašķeļ NV- centru enerģētisko struktūru, radot potenciāli iespējamas Λ sistēmas, kurās var notikt apdzīvotības slazdošana attiecībā pret mikroviļņu diapazona magnētiskā dipola pārejām NV- centra elektroniskajā pamatstāvoklī. NV- centra ar apkārtējiem n 13C atomu kodoliem sistēmas enerģētiskā struktūra aprakstīta, izmantojot spina Hamlitoniāņa metodi. Izveidota datorprogramma optiski reģistrējamo magnētisko rezonanšu modelēšanai. Rezultātā iegūti optiski reģistrējamo magnētisko…
Tumšo un gaišo stāvokļu izpēte reālās un hipotētiskās atomārās sistēmās
2012
Tumšo stāvokļu veidošanās ir pamatā tādām parādībām kā elektromagnētiski inducētā caurspīdība un lāzerģenerācija bez populācijas inversijas. LU Lāzercentrā tiek pētītas magneto-optiskās rezonanses, kuru pamatā ir tumšo stāvokļu veidošanās atomārās sistēmās. Bakalaura darba mērķis ir izpētīt tumšo stāvokļu veidošanās nosacījumus dažādās atomārās sistēmās, pie dažādi polarizētas ierosinošās gaismas. Mērķa sasniegšanai izvirzītie uzdevumi ir speciālās literatūras analīze, datorprogrammas izveide tumšo stāvokļu pētīšanai, tumšo stāvokļu izpēte reālās un atbilstošās hipotētiskās atomārās sistēmās. Rezultātā iegūti tumšo stāvokļu veidošanās nosacījumi divu līmeņu sistēmām. Atslēgvārdi: tumšais st…