Electron spin resonance of erbium in gallium nitride

We performed electron spin resonance (ESR) measurements on Er-doped single GaN crystals synthesized from the solution of nitrogen in liquid gallium un der high pressure of Na The axial Er3+ spectrum was observed with g(paralle l to) = 2.861 +/- 0.003, g(perpendicular to) = 7.645 +/- 0.003, A(parallel to) = (110 +/- 5) x 10(-4)cm(-1), and A(perpendicular to) = (290 +/- 5) x 1 0(-4) cm(-1). The magnitude of an average g-factor g(av) = 1/3(g(parallel t o) +/- 2g(perpendicular to)) was nearly equal to the g(Gamma(7)) ground sta te, as expected for Er3+ ions substituting for Ga in the GaN structure. (C) 2000 Elsevier Science Ltd. All rights reserved.