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Optical Gating of Photoluminescence from Color Centers in Hexagonal Boron Nitride.

ABSTRACT: We report on multicolor excitation experiments with color centers in hexagonal boron nitride at cryogenic temperatures. We demonstrate controllable optical switching between bright and dark states of color centers emitting around 2 eV. Resonant, or quasi-resonant, excitation of photoluminescence also pumps the color center, via a two-photon process, into a dark state, where it becomes trapped. Repumping back into the bright state has a step-like spectrum with a defect-dependent threshold between 2.25 and 2.6 eV. This behavior is consistent with photoionization and charging between optically bright and dark states of the defect. Furthermore, a second zero phonon line, detuned by +0.4 eV, is observed in absorption with orthogonal polarization to the emission, evidencing an additional energy level in the color center.

SUBMITTER: Khatri P

PROVIDER: S-EPMC7304068 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Optical Gating of Photoluminescence from Color Centers in Hexagonal Boron Nitride.

Khatri Prince P Ramsay Andrew J AJ Malein Ralph Nicholas Edward RNE Chong Harold M H HMH Luxmoore Isaac J IJ

Nano letters 20200515 6

We report on multicolor excitation experiments with color centers in hexagonal boron nitride at cryogenic temperatures. We demonstrate controllable optical switching between bright and dark states of color centers emitting around 2 eV. Resonant, or quasi-resonant, excitation of photoluminescence also pumps the color center, via a two-photon process, into a dark state, where it becomes trapped. Repumping back into the bright state has a step-like spectrum with a defect-dependent threshold between ...[more]

PMID: 32383892

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