Directional Amplification with a Josephson Circuit
Abstract
Nonreciprocal devices perform crucial functions in many low-noise quantum measurements, usually by exploiting magnetic effects. In the proof-of-principle device presented here, on the other hand, two on-chip coupled Josephson parametric converters (JPCs) achieve directionality by exploiting the nonreciprocal phase response of the JPC in the transmission-gain mode. The nonreciprocity of the device is controlled in situ by varying the amplitude and phase difference of two independent microwave pump tones feeding the system. At the desired working point and for a signal frequency of 8.453 GHz, the device achieves a forward power gain of 15 dB within a dynamical bandwidth of 9 MHz, a reverse gain of 6 dB, and suppression of the reected signal by 8 dB. We also nd that the amplier adds a noise equivalent to less than 1.5 photons at the signal frequency (referred back to the input). It can process up to 3 photons at the signal frequency per inverse dynamical bandwidth. With a directional amplier operating along the principles of this device, qubit and readout preamplier could be integrated on the same chip.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 2013
- Accession Number
- AD1067335
Entities
People
- Baleegh Abdo
- Katrina Sliwa
- Luigi Frunzio
- Michel Devoret
Organizations
- Yale University