TY  - JOUR
AU  - Viola, G.
AU  - DiVincenzo, David
TI  - Hall Effect Gyrators and Circulators
JO  - Physical review / X
VL  - 4
SN  - 2160-3308
CY  - College Park, Md.
PB  - APS
M1  - FZJ-2014-05508
SP  - 021019
PY  - 2014
N1  -  Erratum Phys. Rev. X 4, 039902 (2014)
AB  - The electronic circulator and its close relative the gyrator are invaluable tools for noise management and signal routing in the current generation of low-temperature microwave systems for the implementation of new quantum technologies. The current implementation of these devices using the Faraday effect is satisfactory but requires a bulky structure whose physical dimension is close to the microwave wavelength employed. The Hall effect is an alternative nonreciprocal effect that can also be used to produce desired device functionality. We review earlier efforts to use an Ohmically contacted four-terminal Hall bar, explaining why this approach leads to unacceptably high device loss. We find that capacitive coupling to such a Hall conductor has much greater promise for achieving good circulator and gyrator functionality. We formulate a classical Ohm-Hall analysis for calculating the properties of such a device, and show how this classical theory simplifies remarkably in the limiting case of the Hall angle approaching 90°. In this limit, we find that either a four-terminal or a three-terminal capacitive device can give excellent circulator behavior, with device dimensions far smaller than the ac wavelength. An experiment is proposed to achieve GHz-band gyration in millimeter (and smaller) scale structures employing either semiconductor heterostructure or graphene Hall conductors. An inductively coupled scheme for realizing a Hall gyrator is also analyzed.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000336121400001
DO  - DOI:10.1103/PhysRevX.4.021019
UR  - https://juser.fz-juelich.de/record/171954
ER  -