TY - JOUR T1 - Evidence for population inversion in excited electron states of a double barrier resonant tunneling structure JO - Applied Physics Letters PY - 1994/05/02 AU - Cockburn JW AU - Skolnick MS AU - Whittaker DM AU - Buckle PD AU - Willcox ARK AU - Smith GW ED - DO - DOI: 10.1063/1.111627 PB - AIP Publishing VL - 64 IS - 18 SP - 2400 EP - 2402 Y2 - 2025/05/09 ER -