[1] Korea Univ, Dept Elect & Comp Engn, Seoul 136075, South Korea
[2] Seoul Natl Univ, Inst Quantum Informat Proc & Syst, Seoul 130743, South Korea
[3] Seoul Natl Univ, Sch Elect Engn, Seoul 151742, South Korea
[4] Seoul Natl Univ, Inter Univ Semicond Res Ctr, Seoul 151742, South Korea
[5] Arizona State Univ, Dept Elect Engn, Tempe, AZ 85287 USA
[6] Arizona State Univ, Ctr Solid State Elect Res, Tempe, AZ 85287 USA