FREQUENCY-DEPENDENT DEPHASING OF N-V CENTERS IN DIAMOND

In this paper, we report on high-resolution magneto-optical double-resonance experiments on the 3A --> 3E zero-phonon line (ZPL) transition of the N-V center in diamond. It is demonstrated that hole burning of the ZPL absorption (at 637 nm) is achieved by resonant microwave excitation of the zero-field spin transition of the N-V center in its triplet (3A) ground state. The results are compatible with the idea of partial correlation of the absolute energies in the initial (3A) and final (3E) state involved in the optical transition. Moreover, focus is on the pure spin dephasing characteristics of N-V centers in their 3A ground state upon narrow-band (approximately 1 MHz) laser excitation. A dependence of the spin dephasing rate on the laser wavelength, used for excitation within the ZPL absorption, is found. The results are discussed in terms of microscopic strain in the diamond lattice.