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تسجيل مستخدم جديدPhotoluminescence from voids created by femtosecond laser pulses inside cubic-BN
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Photoluminescence (PL) from femtosecond laser modified regions inside cubic-boron nitride (c-BN) was measured under UV and visible light excitation. Bright PL at the red spectral range was observed, with a typical excited state lifetime of $sim 4$~ns. Sharp emission lines are consistent with PL of intrinsic vibronic defects linked to the nitrogen vacancy formation (via Frenkel pair) observed earlier in high energy electron irradiated and ion-implanted c-BN. These, formerly known as the radiation centers, RC1, RC2, and RC3 have been identified at the locus of the voids formed by single fs-laser pulse. The method is promising to engineer color centers in c-BN for photonic applications.
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