Tunnel junctions in microfluidic arrays for molecular recognition
Embodiments of the present technology include a system for analyzing a molecule. The system may include a device. The device includes a first conductive element, a second conductive element, and an insulating layer. The insulating layer may be tapered in a direction to reach a minimum thickness at a first end of the device. The insulating layer is disposed between the first conductive element and the second conductive element. The device may include a voltage source in electrical communication with the first conductive element and the second conductive element. The device may also include an electrical meter in electrical communication with the voltage source, the first conductive element, and the second conductive element.
1. A system for analyzing a molecule, the system comprising a device, the device comprising:
a first conductive element;
a second conductive element;
an insulating layer tapered in a direction to reach a minimum thickness at a first end of the device, the insulating layer disposed between the first conductive element and the second conductive element;
a voltage source in electrical communication with the first conductive element and the second conductive element; and
an electrical meter in electrical communication with the voltage source, the first conductive element, and the second conductive element.
2. The system of claim 1 , wherein:
the direction is a first direction,
further comprising:
a pair of electrodes configured to create an electric field in a second direction orthogonal to the first direction, wherein the second direction is parallel to an axis that passes through the first conductive element, and the insulating layer.
3. The system of claim 1 , wherein:
the direction is a first direction,
further comprising:
an instrument configured to create a pressure-driven fluid flow in a second direction orthogonal to the first direction, wherein the second direction is parallel to an axis that passes through the first conductive element, the insulating layer, and the second conductive element.
4. The system of claim 1 , wherein the first conductive element comprises a metal, the second conductive element comprises a metal, and the insulating layer is a dielectric.
5. The system of claim 1 , wherein the insulating layer comprises alumina, hafnia, silicon nitride, or silicon oxide.
6. The system of claim 1 , wherein:
the first conductive element, the second conductive element, and the insulating layer are disposed on a surface of an insulating substrate, and
the direction is orthogonal to the surface of the insulating substrate.
7. The system of claim 1 , wherein:
the first conductive element, the second conductive element, and the insulating layer are disposed on a surface of an insulating substrate, and
the direction is parallel to the surface of the insulating substrate.
8. The system of claim 1 , further comprising a plurality of devices in an array that includes the device.
9. The system of claim 8 , wherein the array is configured such that the molecule contacts the plurality of devices when driven by an electric field or a pressure-driven fluid flow orthogonal to the direction.
10. The system of claim 1 , wherein:
the device is a first device,
the system comprises a second device identical to the first device,
the first device comprises a second end opposite the first end of the first device,
the second device comprises a second end opposite the first end of the second device, and
the first device and the second device are disposed on a surface of an insulating substrate such that:
the first end of the first device is closer to the first end of the second device than the second end of the second device, and
the first end of the second device is closer to the first end of the first device than the second end of the first device.
11. The system of claim 1 , wherein:
the first conductive element and the second conductive element are each tapered such that the maximum thickness of each element is not at the first end,
the first conductive element and the second conductive element are not separated by the insulating layer at a second end opposite the first end.
12. The system of claim 1 , further comprising a liquid, wherein a portion of the device is submerged in the liquid.