We report novel GaN detectors grown by molecular beam epitaxy on Si(11
1) substrates. Wurtzite structure epitaxial GaN exhibits room-temperat
ure photoluminescence with a band-edge-related emission width as narro
w as 7 nm and intensities comparable to high quality layers grown on s
apphire by metalorganic chemical vapor deposition. Spectral response o
f lateral geometry Schottky detectors shows a sharp cutoff at 365 nm w
ith peak responsivities of approximate-to 0.05 A/W at 0V, and approxim
ate-to 0.1 A/W with a -4V bias. The dark current is approximate-to 60
nA at -2V bias. the noise equivalent power is estimated to be 3.7x10(-
9)W over the responsible bandwidth of 2.2 MHz.