1. (1) S. Datta and B. Das : “Electronic analog of the electro-optic modulator”, Appl. Phys. Lett., Vol. 56, pp. 665-667 (1990)
2. (2) R. Fiederling, M. Keim, G. Reuscher, W. Ossau, G. Schmidt, A. Waag, and L. W. Molenkamp : “Injection and detection of a spin-polarized current in a light-emitting diode”, Nature, Vol. 402, pp. 787-790 (1999)
3. (3) Y. Ohno, D. K. Young, B. Beschoten, F. Matsukura, H. Ohno, and D. D. Awschalom : “Electron spin injection in a ferromagnetic semiconductor heterostructure”, Nature, Vol. 402, pp. 790-792 (1999)
4. (4) G. Schmidt, D. Ferrand, L. W. Molenkamp, A. T. Filip, and B. J. van Wees : “Fundamental obstacle for electrical spin injection from a ferromagnetic metal into a diffusive semiconductor”, Phys. Rev. B, Vol. 62, pp. R4790-R4793 (2000)
5. (5) E. I. Rashba : “Theory of electrical spin injection: Tunnel contacts as a solution of the conductivity mismatch problem”, Phys. Rev. B, Vol. 62, pp. R16267-R16270 (2000)