Development of a Broadband NbTiN Traveling Wave Parametric Amplifier for MKID Readout

Broadband parametric amplifiers based on nonlinear kinetic inductance artificial transmission lines

“…However, the ∼ 10 µA critical current of the junctions limits the dynamic range of these devices and excludes them from some important applications, such as the multiplexed readout of thousands of qubits or detectors. In addition, fabricating a large number (> 1000) of junctions with high yield is a nontrivial task.Recently, another type of broadband parametric amplifier based on the nonlinear kinetic inductance of NbTiN transmission lines has been proposed [17,18,[20][21][22]. These devices are simple to fabricate, requiring only one lithography step (patterning of the NbTiN film).…”

“…In contrast with reflectiontype resonant JPAs, the traveling-wave architecture of the NbTiN amplifier eliminates the need for a circulator, enabling on-chip integration with a detector or qubit. In previous work, NbTiN amplifiers were realized as long coplanar waveguide (CPW) transmission lines, with >20 dB gain over several GHz bandwidth [18]. Despite the excellent gain performance, the CPW amplifier has a few drawbacks.…”

Quantum simulation of traversable wormhole spacetimes in a dc-SQUID array

“…The assumption that a photon is traveling along the left part of the transmission line only during a few nanoseconds would imply a transmission line length around 10 cm and thus a number of several thousand SQUIDs. Transmission lines of more than 2 m [35] and arrays of more than 500 SQUIDs [36] have already been achieved in the laboratory. These numbers have been derived within the assumption that the accelerations are instantaneous.…”

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

“…Quantum limited amplifiers that are based on the non-linearity provided by Josephson junctions have been developed in various designs. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] Nondegenerate three-wave mixing, a key operation, is realized by the Josephson ring modulator (JRM), which is a ring of four identical Josephson junctions. 21,22 This element is at the core of several tools able to generate and manipulate quantum microwave modes such as phase preserving amplifiers, [23][24][25] non-local entanglement generators, 26 frequency converters, 27 quantum memories, 28 or circulators.…”

“…12,13,15,17 Recently, degenerate Josephson Parametric Amplifiers have reached more than 15 dB gain over a 700 MHz bandwidth in an all lumped-element based design 17 while 15 dB gain over GHz bandwidth has been reported in a TiN traveling wave parametric amplifiers. 13,14 The constraints on the parameters of the Josephson mixer are similar in origin to those of its degenerate cousin, the Josephson Parametric Amplifier, 32,33 but with some differences. 22 First, there is an upper bound on the energy that is stored in the p pump mode, originating from the small flux u p assumption in the three-wave mixing term H mix .…”