APPLICATIONS OF TECHNOLOGY:
- Superconducting single photon detectors
- Transition edge detectors
- Superconducting transistors
- SQUID magnetometry
- Chemical detectors
- Photovoltaic devices
- Quantum computation
- Applications limited only by dopant used
- Ease of production
- Ease of measurement
- Tunability by a simple electric field
- Can fabricate wafer-scale devices
- Inexpensive, non-toxic dopants are effective
Alex Zettl and colleagues at Berkeley Lab have induced a two-dimensional superconducting order on a graphene sheet and tuned its material properties—transition temperature, critical field, and critical current—via an electrostatic gate. The technology enables the properties of diverse electronic devices to be controlled by the simple addition of dopants (or coatings) combined with the application of an electric field via external circuitry. In addition to control, properties of graphene and the dopant used enable measurement of device properties for applications such as photoelectric characteristics, chemical specificity, spintronics and superconductivity.
One of the most interesting and potentially useful properties of graphene is its electric-field effect, which allows the carrier density to be tuned via an external voltage control signal. The Berkeley Lab technology exploits this gating effect to change the coupling between order parameter inducing islands. Normally, the order parameter is difficult to tune, necessitating changes in material composition or pressure or the application of large magnetic field. This technology bypasses these difficulties and provides a less complicated alternative to material tuning.
DEVELOPMENT STAGE: Bench scale testing conducted.
STATUS: Patent pending. Available for licensing or collaborative research.
FOR MORE INFORMATION:
Kessler, B.M., Girit, Ç.Ö., Zettl, A., Bouchiat, V. Tunable Superconducting Phase Transition in Metal-Decorated Graphene Sheets. Phys. Rev. Lett. 104 (4), 1-4 (2010).
SEE THESE OTHER BERKELEY LAB TECHNOLOGIES IN THIS FIELD:
Tunable Thermal Link, IB-2337
REFERENCE NUMBER: JIB-2697