Impedance matched gyrators with edge magnetoplasmons

Non-reciprocal Cryo-CMOS components addresses key challenges in cryogenic experiments, such as low-power signal routing, amplification, and qubit readout. Edge magnetoplasmons (EMPs) offer inherent chirality and directional propagation, thus making them ideal candidates for non-reciprocal devices.

It has been predicted [1] that EMP gyrators offer a significant reduction in size compared to traditional ferrite-based components particularly for the low frequency range below 1 GHz. Moreover, with careful considerations regarding the device geometry, it is possible to have 50 Ω impedance matching, critical for reducing losses.

We present experiments from 3 gyrator devices of different sizes on a GaAs/AlGaAs heterostructure with terminals which are capacitively coupled to the 2D electron gas, avoiding losses from ohmic contacts. We have measured transmission parameters in a dilution refrigerator as a function of magnetic field and find good agreement with theory once the parasitics and coupling capacitances are taken into account. These results open the way for a new generation of non-reciprocal and self-impedance matched devices for applications such as gyrators or circulators.

[1] S. Bosco et al. Phys. Rev. Applied 7, 024030 (2017)

Thanks to C. Reich and W. Wegscheider from ETHZ for providing the heterostructure.