A compact design for the Josephson mixer: The lumped element circuit

Abstract

International audienc

Quantum simulation of ultrastrongly coupled bosonic modes using superconducting circuits

“…The condition that √ ξ a ξ b Q a Q b > 4 sets constraints on the device similar to the ones needed to realize a quantum limited amplifier using the Josephson mixer [32,55] and is perfectly realistic. The parameters we chose in Fig.…”

Time-multiplexed amplification in a hybrid-less and coil-less Josephson parametric converter

“…It is used to perform high-fidelity, quantum nondemolition measurement of superconducting qubits [4], track their quantum trajectories in realtime [5, 6], enable feedback [7], transduce quantum information via noiseless frequency conversion [8,9], and generate two-mode squeezed states of the microwave field [10]. JPCs also have the potential of serving as remote entanglers [11] in distributed quantum networks.However, despite the many useful applications of the JPC, state-of-the-art JPCs [3,12,13] suffer from three main limitations that hinder their use in scalable quantum architectures, i.e., narrow dynamical bandwidth on the order of 10 MHz at 20 dB of gain, low saturation input power on the order of a few microwave photons per inverse dynamical bandwidth, both of which do not enable the readout of more than one qubit per JPC, and lastly the large footprint of the auxiliary drive and bias circuit needed for the operation of the device.Here, we report on a new design and device which significantly simplifies the circuit and reduces the footprint of the JPC without degrading its performance. The new design is expected to not only promote scalability, but also to make it possible to realize quantum-limited directional amplifiers and noiseless circulators (as have been featured in recent works [14-17]).…”

“…However, despite the many useful applications of the JPC, state-of-the-art JPCs [3,12,13] suffer from three main limitations that hinder their use in scalable quantum architectures, i.e., narrow dynamical bandwidth on the order of 10 MHz at 20 dB of gain, low saturation input power on the order of a few microwave photons per inverse dynamical bandwidth, both of which do not enable the readout of more than one qubit per JPC, and lastly the large footprint of the auxiliary drive and bias circuit needed for the operation of the device.…”

Active protection of a superconducting qubit with an interferometric Josephson isolator

“…Applying such a technique in the case of single-port Josephson parametric amplifiers has successfully yielded bandwidths in the range 0.6 − 0.7 GHz [57,58], which correspond to more than 12-fold enhancement compared to standard designs. Additional enhancements of the device include, (1) reducing its footprint by integrating all components on chip and using lumped-element realization of the JPCs [59] and hybrids [60], (2) unifying the two external ports of the pumps, as shown in Figs. 2e,f. This could be achieved by injecting a single-pump drive into the MPIJIS through an on-chip 90 • hybrid whose two output ports connect to the two-stage pump lines as proposed in Ref.…”