Near-field transducers for focusing light
An apparatus includes a waveguide shaped to direct light to a focal point, and a near-field transducer positioned adjacent to the focal point, wherein the near-field transducer includes a dielectric component and a metallic component positioned adjacent to at least a portion of the dielectric component. An apparatus includes a waveguide shaped to direct light to a focal point, and a near-field transducer positioned adjacent to the focal point, wherein the near-field transducer includes a first metallic component, a first dielectric layer positioned adjacent to at least a portion of the first metallic component, and a second metallic component positioned adjacent to at least a portion of the first dielectric component.
1. An apparatus comprising:
a waveguide shaped to direct light to a focal point; and
a near-field transducer positioned adjacent to the focal point, wherein the near-field transducer includes a dielectric peg, a dielectric enlarged portion, and a metallic component positioned adjacent to at least a portion of the dielectric enlarged portion, wherein the dielectric peg is embedded in the metallic component.
2. The apparatus of claim 1 , wherein the dielectric
peg includes a first end positioned adjacent to an end of the waveguide; and
the dielectric enlarged portion is positioned adjacent to a second end of the peg.
3. The apparatus of claim 2 , wherein the dielectric enlarged portion has a circular, cylindrical or rectangular cross-sectional shape.
4. The apparatus of claim 1 , wherein the waveguide includes a core layer and a cladding layer and the near-field transducer is positioned in the cladding layer.
5. The apparatus of claim 1 , wherein the waveguide includes a core layer and a cladding layer and the near-field transducer is positioned in the core layer.
6. The apparatus of claim 1 , wherein the waveguide includes a core layer embedded in a cladding layer, and the core layer has a rectangular or trapezoidal cross-section.
7. An apparatus comprising:
a waveguide shaped to direct light to a focal point;
a near-field transducer positioned adjacent to the focal point, wherein the near-field transducer includes a dielectric component and a metallic component positioned adjacent to at least a portion of the dielectric, wherein the metallic component comprises first and second nanorods separated by a gap, and the dielectric component is positioned in the gap;
a first metallic wire connected to the first nanorod; and
a second metallic wire connected to the second nanorod.
8. The apparatus of claim 7 , wherein the metallic component surrounds at least a portion of the dielectric component.
9. An apparatus comprising:
a waveguide shaped to direct light to a focal point;
a near-field transducer positioned adjacent to the focal point, wherein the near-field transducer includes a first metallic component, a first dielectric layer positioned adjacent to at least a portion of the first metallic component, and a second metallic component positioned adjacent to at least a portion of the first dielectric component; and
a third metallic component in a gap in the first dielectric layer.
10. The apparatus of claim 9 , wherein the first metallic component of the near-field transducer comprises:
a peg having a first end positioned adjacent to an end of the waveguide; and
an enlarged portion positioned adjacent to a second end of the peg.
11. The apparatus of claim 10 , wherein the enlarged portion has a circular shape.
12. The apparatus of claim 10 , wherein the waveguide includes a core layer and a cladding layer and the near-field transducer is positioned in the cladding layer.
13. The apparatus of claim 10 , wherein the waveguide includes a core layer and a cladding layer and the near-field transducer is positioned in the core layer.
14. The apparatus of claim 9 , wherein the first dielectric layer surrounds at least a portion of the first metallic component, and a second metallic component surrounds at least a portion of the first dielectric component.
15. The apparatus of claim 9 , wherein the first metallic component includes at least one of:
gold, silver, copper, aluminum or alloys thereof.
16. The apparatus of claim 9 , wherein the first dielectric component includes at least one of:
alumina, tantala, titania, magnesium oxide, silicon oxinitride, silicon nitride, or combinations thereof.
17. An apparatus comprising:
a waveguide shaped to direct light to a focal point;
a near-field transducer positioned adjacent to the focal point, wherein the near-field transducer includes a first metallic component, a first dielectric layer positioned adjacent to at least a portion of the first metallic component, and a second metallic component positioned adjacent to at least a portion of the first dielectric component; and
a second dielectric layer surrounding at least a portion of the second metallic component.
18. The apparatus of claim 17 , further comprising:
a third metallic component in a gap in the first dielectric layer; and
a fourth metallic component in a gap in the first dielectric layer.