Erlangen 2018 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

Q: Fachverband Quantenoptik und Photonik

Q 50: Quantum Gases (Bosons) V

Q 50.6: Talk

Wednesday, March 7, 2018, 15:15–15:30, K 2.020

A noiseless matter wave readout amplifier for atom interferometry — •Daniel Linnemann, Philipp Kunkel, Helmut Strobel, Maximilian Prüfer, Stefan Lannig, Rodrigo Rosa-Medina Pimentel, Martin Gärttner, Thomas Gasenzer, and Markus K. Oberthaler — Kirchhoff-Institut für Physik, Im Neuenheimer Feld 227, Heidelberg

We present a quantum-enhanced atom interferometer whose output state is magnified by a noiseless readout amplifier for matter waves. In presence of spurious technical detection noise, subsequently amplifying the interferometer's output can improve the overall sensitivity.

The amplification process which usually degrades the signal-to-noise ratio by at least three decibels, is rendered noiseless in our scheme by entangling the amplifier with its input. In this way, non-classical correlations are leveraged in two respects: they enhance the interferometer's phase sensitivity and facilitate the readout.

Experimentally, we employ spin exchange in a Bose-Einstein condensate as the underlying entangling interaction. This scattering process among spins can be understood as parametric amplification. We detail the noise characteristics when using spin exchange as a phase-preserving linear amplifier. Attaching the amplification stage to an interferometer, we explicitly demonstrate that quantum-enhanced phase sensitivity is maintained even for large magnifications of the signal.