1994, Science, 264, 553, 10.1126/science.264.5158.553
1996, Appl. Phys. Lett., 68, 3680, 10.1063/1.115741
1972, J. Appl. Phys., 43, 2327, 10.1063/1.1661499
1995, Appl. Phys. Lett., 68, 1745
1990, IEEE Photonics Technol. Lett., 2, 614, 10.1109/68.59328
1989, Appl. Phys. Lett., 55, 1606, 10.1063/1.102254