Related Experiment Video
Updated: Jun 19, 2026
09:13
Plasmonic Trapping and Release of Nanoparticles in a Monitoring Environment
Published on: April 4, 2017
Near-field nanoimaging by nanoscale photodetector array
Boyang Liu1, Ki Young Kim, Yicheng Lai
1Department of Electrical Engineering and Computer Science, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA. boyangliu2008@u.northwestern.edu
Optics Letters
|November 3, 2009
Summary
This study demonstrates near-field nanoimaging using a nanoscale photodetector (NPD) array with subwavelength pixels. The NPD array achieved 150 nm resolution in simulations and 390 nm experimentally for advanced optical imaging applications.
Area of Science:
- Optics and Photonics
- Nanotechnology
- Materials Science
Background:
- Near-field nanoimaging offers high-resolution optical microscopy beyond the diffraction limit.
- Existing nanoimaging techniques face challenges in resolution, speed, and integration.
- Nanoscale photodetector (NPD) arrays present a potential solution for advanced imaging.
Purpose of the Study:
- To demonstrate near-field nanoimaging capabilities using a novel nanoscale photodetector (NPD) array.
- To investigate the imaging resolution and performance characteristics of the NPD array.
- To validate the fabrication and functionality of subwavelength-dimensioned detector pixels.
Main Methods:
- Fabrication and characterization of a nanoscale photodetector (NPD) array with subwavelength pixels.
- Active-media finite-difference time-domain (FDTD) simulations to predict imaging resolution.
- Near-field photocurrent microscopy to experimentally assess imaging performance.
Main Results:
- Simulated imaging resolution of 150 nm for 1.55 micrometer light using FDTD.
- Fabricated NPD array with pixels as small as 100 nm wide with 100 nm spacing.
- Experimental demonstration of 390 nm imaging resolution using near-field photocurrent microscopy.
- Measured responsivity of 0.28 A/W at 1.31 micrometer with low dark current.
Conclusions:
- The nanoscale photodetector (NPD) array is a viable technology for high-resolution near-field nanoimaging.
- The demonstrated NPD array enables pixel-addressed imaging with subwavelength resolution.
- Further development of NPD arrays could lead to breakthroughs in optical microscopy and sensing.
