Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Optica Laser Congress (ASSL, LAC, LS&C)

Nonlinear Optical Absorption and Relaxation Kinetics of GR1 Centers in Diamond

Shova D. Subedi, Vladimir Fedorov, Sergey Mirov, Matthew Markham

Published Jan 1, 2020• 0 citations
Publisher

Abstract

We report on saturation of GR1 centers absorption resulting in ~70% inversion. Probe kinetics revealed strong bleaching of ground level followed by relaxation to metastable level with branching ratio ~0.5.
DOI
10.1364/assl.2020.jtu5a.16

Related papers

Study of relaxation dynamics of excited state of GR1 centers in diamond

Shova D. Subedi, Vladimir Fedorov, Sergey Mirov +1 more

We study the decay kinetics of excited state of GR1 center in diamond using 633 nm pump pulse and 658 nm CW probe beam. The absorption saturation followed by a strong absorption of the probe below steady-state transmission level was observed. The recovery of the centers to the original level occurs slowly with ~500 ns time scale and reveals multi-exponential rates with no long-term bleaching or residual absorption. The branching ratio for relaxation process to the ground state and to the metastable state was estimated to be ~ 0.50.

SPIE Solid State Lasers: Technology and Devices•Mar 4, 2021•0 citations

Pump-probe experiments of the excited state dynamics of GR1 centers in diamond

Shova D. Subedi, Vladimir Fedorov, Sergey Mirov +1 more

The 658 nm probe kinetics revealed strong bleaching and multiexponential decay of the excited level with additional relaxation via intersystem crossing. The origin of induced excited state absorption was due to some other center impurity center.

Conference on Lasers and Electro-Optics•Jan 1, 2021•0 citations

Spectroscopy of GR1 centers in synthetic diamonds

Shova D. Subedi, Vladimir Fedorov, Sergey Mirov +1 more

We report on the spectroscopic characterization, absorption saturation, and excited-state dynamics of GR1 centers in synthetic diamonds. The non-linear optical measurements reveal an efficient bleaching of the GR1 center’s ground level under ns-pulsed 633 nm excitation. The maxima of absorption and emission cross sections were estimated to be 4.5 × 10−17 cm2 and 9 × 10−17 cm2 at 630 nm and 780 nm, respectively. The radiative lifetime of the excited level was estimated to be 8.5 ns. The 658 nm probe kinetics uncovered relaxation of 1T2 excited level going predominantly to a metastable state with a lifetime of 220 μs. An induced absorption detected with the use of a highly concentrated diamond sample could be due to up-conversion and photoionization processes in additional impurity-vacancy center with absorption at the short-wavelength tail of GR1. The results presented here indicate that synthetic diamonds with GR1 centers could serve as near infrared gain media or passive Q-switchers for laser cavities over the 633–750 nm spectral range. Optimization of the center concentration and the crystal parameters are required to minimize the induced absorption at the lasing wavelengths.

Optical Materials Express•Feb 12, 2021•20 citations

Saturation spectroscopy of NV− centers in diamond

Shova D. Subedi, Vladimir Fedorov, Sergey Mirov +2 more

We report saturation of NV− centers resulting in ~40% inversion level under 632nm pumping. Δk/ko kinetics revealed long recovery time of NV− centers after photoionization under 532nm pump, which involved different relaxation channels depending on the probe beam wavelengths.

Optica Laser Congress (ASSL, LAC, LS&C)•Jan 1, 2018•4 citations

Resonant excitation of GR 1 in diamond

J. Mazzaschi, J. Barrau, J.C. Bradant +2 more

Journal of Luminescence•Nov 1, 1981•2 citations

Laser spectroscopic characterization of negatively charged nitrogen-vacancy (NV−) centers in diamond

Shova D. Subedi, Vladimir Fedorov, Jeremy M. Peppers +4 more

We report on the spectroscopic and laser characterization of negatively charged nitrogen-vacancy (NV−) centers in diamond. Spectroscopic properties such as absorption and emission spectra as well as kinetics were studied, and parameters such as cross-sections and lifetimes were estimated. A vibronic band of NV0 with zero phonon line (ZPL) at 575 nm was detected under 532 nm pulsed excitation due to the photoionization of NV−. Transmission of 532 nm pump pulses saturate around ∼10%, which is much smaller than the theoretical level. Δk/k0 kinetics revealed slow recovery of NV− centers after photoionization under 532 nm pumping, which involved different relaxation channels depending on the probe beam wavelengths. Localization of the electrons in the metastable state of NV0 centers resulted in higher saturated transmission of 632 nm pump.

Optical Materials Express•Apr 5, 2019•73 citations
We study the decay kinetics of excited state of GR1 center in diamond using 633 nm pump pulse and 658 nm CW probe beam. The absorption saturation followed by a strong absorption of the probe below steady-state transmission level was observed. The recovery of the centers to the original level occurs slowly with ~500 ns time scale and reveals multi-exponential rates with no long-term bleaching or residual absorption. The branching ratio for relaxation process to the ground state and to the metastable state was estimated to be ~ 0.50.
We report on the spectroscopic characterization, absorption saturation, and excited-state dynamics of GR1 centers in synthetic diamonds. The non-linear optical measurements reveal an efficient bleaching of the GR1 center’s ground level under ns-pulsed 633 nm excitation. The maxima of absorption and emission cross sections were estimated to be 4.5 × 10−17 cm2 and 9 × 10−17 cm2 at 630 nm and 780 nm, respectively. The radiative lifetime of the excited level was estimated to be 8.5 ns. The 658 nm probe kinetics uncovered relaxation of 1T2 excited level going predominantly to a metastable state with a lifetime of 220 μs. An induced absorption detected with the use of a highly concentrated diamond sample could be due to up-conversion and photoionization processes in additional impurity-vacancy center with absorption at the short-wavelength tail of GR1. The results presented here indicate that synthetic diamonds with GR1 centers could serve as near infrared gain media or passive Q-switchers for laser cavities over the 633–750 nm spectral range. Optimization of the center concentration and the crystal parameters are required to minimize the induced absorption at the lasing wavelengths.
We report on the spectroscopic and laser characterization of negatively charged nitrogen-vacancy (NV−) centers in diamond. Spectroscopic properties such as absorption and emission spectra as well as kinetics were studied, and parameters such as cross-sections and lifetimes were estimated. A vibronic band of NV0 with zero phonon line (ZPL) at 575 nm was detected under 532 nm pulsed excitation due to the photoionization of NV−. Transmission of 532 nm pump pulses saturate around ∼10%, which is much smaller than the theoretical level. Δk/k0 kinetics revealed slow recovery of NV− centers after photoionization under 532 nm pumping, which involved different relaxation channels depending on the probe beam wavelengths. Localization of the electrons in the metastable state of NV0 centers resulted in higher saturated transmission of 632 nm pump.