Abstract

A photodetector operating with subwavelength spatial resolution is presented. The active region of this detector is defined by the pn-interface region of a highly doped GaAs homojunction. The cleavage plane normal to the interface defines a line detector with high spatial resolution. The actual resolution was tested using a near-field scanning optical microscope. An Al-coated tapered optical fiber of nominal aperture of 60 nm was scanned in the optical near-field vicinity across the active region of the junction. The photocurrent was measured as a function of the position of the fiber tip relative to the cleaved GaAs pn-junction. The width of the observed peak in photocurrent is found to be highly asymmetric with respect to the p or n side of the junction. The reason for this asymmetry is discussed in terms of diffusion length of minority carriers in the n- and p-GaAs close to the suface.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.