Coherent exciton–biexciton dynamics in GaN

K. Kyhm; R. A. Taylor; J. F. Ryan; T. Aoki; M. Kuwata-Gonokami; B. Beaumont; P. Gibart

doi:10.1103/PhysRevB.65.193102

Coherent exciton–biexciton dynamics in GaN

K. Kyhm, R. A. Taylor, J. F. Ryan, T. Aoki, M. Kuwata-Gonokami, B. Beaumont, and P. Gibart

Phys. Rev. B 65, 193102 – Published 22 April 2002

Abstract

Spectrally resolved and time-integrated four-wave mixing are used to measure the polarization dependence of biexcitonic signals and quantum beats between two- $A$ -exciton ${(X}_{A} X_{A}^{*})$ and A-biexciton ${(X}_{A} X_{A})$ states in a high-quality GaN epilayer. Mixed beats with two periods are observed: the first beating period corresponds to the energy splitting between $X_{A} X_{A}^{*}$ and $X_{A} X_{A};$ the second period corresponds to beating between A excitons ${(X}_{A})$ and donor bound excitons ${(D}^{0} X) .$ We also measure the polarization-dependent B-biexciton ${(X}_{B} X_{B})$ signal. The effective masses for the A and B holes are deduced from the binding energy.