Tunneling involving defects in LPE In1−xGaxP1−zAsz(x∼0.12, z∼0.26) double-heterojunction lasers

Abstract

Defect-assisted (’’two-step’’) tunneling is observed in the I-V and dI/dV characteristics of LPE In1−xGaxP1−zAsz double-heterojunction laser diodes (Jth∼4.7×102 A/cm2, λ∼1.05 μm, 77 °K). The change in conductance (’’turn-off’’) at zero bias due to resonant-elastic tunneling, and a related change at 40–60 mV involving acceptor states, are compared with similar data on Zn-diffused InxGa1−xAs laser diodes, and indicate that the Zn dopant in either type of laser diode is the main source of the defects involved in the two-step tunneling.