Strong Kinetic-Inductance Kerr Nonlinearity with Titanium Nitride Nanowires
Chaitali Joshi, Wen‐Yuan Chen, H. G. LeDuc, Peter K. Day, Mohammad Mirhosseini
Abstract
The kinetic inductance of charge carriers in disordered superconductors provides a broadband low-loss source of nonlinear electromagnetic response. This work investigates TiN nanowires as an alternative to Josephson junctions for applications involving elevated temperatures, higher frequencies, and strong magnetic fields. An extreme nanowire geometry for TiN microwave resonators leads to current-density concentration and enhanced self-Kerr coefficient, yielding a nonlinearity-to-loss ratio as high as 21% and quality factor exceeding 10,000. Such devices may find application in quantum frequency conversion of microwave photons, and with improvement might attain strong quantum nonlinearity.