Graphene-Insulator-Graphene Active THz Devices
Berardi Sensale-Rodriguez
Discovery:
Graphene-based
plasmonic
structures composed of graphene-insulatorgraphene can provide gain at THz frequencies
due to interplay between plasmons and
resonant-tunneling.
Approach: Developed DC model of the
structure based on quantum phenomena, a
transmission line equivalent model and device
analysis employing microwave circuit design
techniques.
Results and Significance: Demonstrated that
graphene-insulator-graphene structures can
provide stable power gain (>7dB) at THz
frequencies ( f > 2 THz), which is well above
the fT of traditional high frequency electronic
devices. The achievable power gain in these
structures can surpass what is possible in RTD
gated-HEMT structures employing traditional
semiconductors.
Left: High frequency model of a gated grapheneinsulator-graphene structure; the device can be
represented as an active transmission line .
Right: Transducer power gain as a function of
frequency in amplifier configuration; design for
maximum stable gain at 2 THz.
Applied Physics Letters 103, 123109 (2013)
Principal Investigators: Anil Virkar, Ajay Nahata & Brian Saam