Photoluminescence from voids created by femtosecond laser pulses inside cubic-BN

TL;DR

This study investigates photoluminescence from voids created by femtosecond laser pulses inside cubic-boron nitride, revealing defect-related emission lines and potential for photonic applications.

Contribution

It demonstrates the formation of intrinsic vibronic defects linked to nitrogen vacancies in laser-modified regions of c-BN, enabling defect engineering for photonics.

Findings

Bright red photoluminescence observed with ~4 ns lifetime

Sharp emission lines linked to nitrogen vacancy-related defects

Void regions can host radiation centers RC1, RC2, RC3

Abstract

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.