Detection of electromagnetic radiation using nonlinear materials

Patent metadata

Field	Value
Publication number	US-10024723-B2
Application number	US-201615156115-A
Country	US
Kind code	B2
Filing date	May 16, 2016
Priority date	Jul 3, 2012
Publication date	Jul 17, 2018
Grant date	Jul 17, 2018

Abstract

An apparatus for detecting electromagnetic radiation within a target frequency range is provided. The apparatus includes a substrate and one or more resonator structures disposed on the substrate. The substrate can be a dielectric or semiconductor material. Each of the one or more resonator structures has at least one dimension that is less than the wavelength of target electromagnetic radiation within the target frequency range, and each of the resonator structures includes at least two conductive structures separated by a spacing. Charge carriers are induced in the substrate near the spacing when the resonator structures are exposed to the target electromagnetic radiation. A measure of the change in conductivity of the substrate due to the induced charge carriers provides an indication of the presence of the target electromagnetic radiation.

First claim

What is claimed is:

1. An image sensing method, comprising:
A) irradiating a detector element, disposed on a first side of a substrate having a depletion region, with electromagnetic radiation at least partially reflected from an object of interest, the detector element comprising a resonator structure defined by two conductive structures separated by a spacing;
B) in response to A), generating charge carriers near the spacing and in the depletion region of the substrate, based on an enhanced electric field induced in the spacing by a resonant response of the resonator structure to at least one frequency component in the electromagnetic radiation, the at least one frequency component having a frequency of about 100 GHz to about 100 THz; and
C) electronically generating an image of at least a portion of the object of interest based at least in part on the generated charge carriers,
wherein B) comprises generating electron-hole pairs near the spacing and in the depletion region of the substrate,
the substrate is back-thinned, and
the backthinning of the substrate causes the electron-hole pairs to be formed in the depletion region, and wherein a potential in the depletion region separates the electron-hole pairs, thereby facilitating measurement of the electron-hole pairs to provide an indication of the presence of the target electromagnetic radiation.

2. The image sensing method of claim 1 , wherein C) comprises measuring, via a circuit element disposed on a second side of the substrate, a change of conductivity induced at least partially by the generated charge carriers, wherein the second side of the substrate is opposite to the first side of the substrate.

3. The imaging sensing method of claim 1 , wherein A) comprises irradiating a first resonator structure and a second resonator structure in the detector element with the electromagnetic radiation, wherein the first resonator structure has a first dimension different from a second dimension of the second resonator structure so as to facilitate spectroscopic sensing.

4. The imaging sensing method of claim 1 , wherein A) comprises irradiating the resonator structure formed as a split-ring resonator structure including at least two spacings formed between corresponding pairs of the at least two conductive structures.

5. The imaging sensing method of claim 1 , wherein A) comprises irradiating a plurality of resonant structures arranged in an alternating interdigitated arrangement such that a portion of a first resonator structure in the plurality of resonator structures is disposed within a spacing of, and not in physical contact with, a second resonator structure in the plurality of resonator structures; and
wherein the portion of the first resonator structure is oriented in a direction parallel to a side of the second resonator structure neighboring the spacing.

6. The imaging sensing method of claim 1 , wherein A) comprises irradiating the resonator structure having at least one dimension less than a wavelength of the at least one frequency component in the electromagnetic radiation.

7. The imaging sensing method of claim 1 , wherein A) comprises irradiating the two conductive structures configured in a wedge morphology.

8. The imaging sensing method of claim 1 , wherein A) comprises irradiating the resonator structure including at least four conductive structures formed in a cross pattern separated by the spacing.

9. The imaging sensing method of claim 1 , wherein A) comprises irradiating the spacing having a wide of about 1.0 μm to about 2.5 μm.

10. The imaging sensing method of claim 1 , wherein A) comprises irradiating a first conductive structure and a second conductive structure disposed on the substrate;
wherein a surface of the substrate comprising the first conductive structure and the second conductive structure lies in an y-z plane;
wherein the first conductive structure and the second conductive structure are aligned in a longitudinal antenna arrangement along a z-direction of the substrate; and
wherein the spacing separates an end of the first conductive structure from an end of the second conductive structure in the z-direction.

11. The imaging sensing method of claim 1 , further comprising:
measuring a polarization of the electromagnetic radiation based at least in part on the generated charge carriers.

12. The imaging sensing method of claim 1 , further comprising:
measuring a magnitude of the electromagnetic radiation based at least in part on the generated charge carriers.

13. The imaging sensing method of claim 1 , further comprising:
measuring a spatial profile of the electromagnetic radiation based at least in part on the generated charge carriers.

Assignees

• Massachusetts Inst Technology
• Univ Boston

Inventors

• Hwang Harold Y
• Liu Mengkun
• Averitt Richard D
• Nelson Keith A
• Sternbach Aaron
• Fan Kebin

Classifications

• G01J2005/202

  Arrays · CPC title

• G01J2005/0077

  Imaging · CPC title

• G01J5/20 Primary

  using resistors, thermistors or semiconductors sensitive to radiation, e.g. photoconductive devices · CPC title

• G01J2005/286

  Arrangement of conductor therefor · CPC title

• G01J5/28 Primary

  using photoemissive or photovoltaic cells · CPC title