  To achieve a high-density electron-hole plasma in group-III nitrides for
efficient light emission, we propose a planar two-dimensional (2D) p-i-n
structure that can be created in selectively-doped superlattices and quantum
wells. The 2D p-i-n structure is formed in the quantum well layers due to
efficient activation of donors and acceptors in the laterally doped barriers.
We show that strongly non-equilibrium 2D electron-hole plasma with density
above $10^{12} cm^{-2}$ can be realized in the i-region of the laterally biased
p-i-n structure, enabling the formation of interband population inversion and
stimulated emission from such a LAteral Current pumped Emitter (LACE). We
suggest that implementation of the lateral p-i-n structures provides an
efficient way of utilizing potential-profile-enhanced doping of superlattices
and quantum wells for electric pumping of nitride-based lasers.
