TY - JOUR AU - Y. An AU - Steven Cundiff BT - Applied Physics Letters DA - 2002 DO - 10.1063/1.1533122 PY - 2002 EP - 5174 T2 - Applied Physics Letters TI - Bulk and surface contributions to resonant second-harmonic generation from Si(001) surfaces VL - 81 SN - 00036951 ER -