Strongly Photonic Macroporous Gallium Phosphide Networks
Frank J. P. ,
Schuurmans,
1*
Daniël Vanmaekelbergh,
2
Jao van de Lagemaat,
2
Ad Lagendijk
1
A photo-assisted electrochemical etching technique to fabricate
macropores in single-crystalline gallium phosphide (GaP) with variable
porosity has been developed. Scanning electron microscopy and x-ray
diffraction experiments confirm that the material consists of
three-dimensional, interconnected random networks with pore sizes of
about 150 nanometers. Optical transmission measurements demonstrate
that the nonabsorbing disordered structures strongly scatter light. The
photonic strength is controlled by filling the pores with liquids of
different refractive indices. Macroporous gallium phosphide filled with
air has the highest scattering efficiency for visible light.
1 Van der Waals-Zeeman Instituut, Universiteit
van Amsterdam, Valckenierstraat 65, 1018 XE Amsterdam, The Netherlands.
2 Debye Instituut, Universiteit Utrecht, Post Office
Box 80000, 3508 TA Utrecht, The Netherlands.
*
To whom correspondence should be addressed. E-mail:
schuurma{at}phys.uva.nl
Present address: Basic Sciences Center, National
Renewable Energy Laboratory, 1617 Cole Boulevard, Golden, CO
80401-3393, USA.
