Sensing with quantum error correction


  Tuvia Gefen [1]  ,  David A. Herrera-Marti [1]  ,  Nadav Katz [1]  ,  Dorit Aharonov [2]  ,  Alex Retzker [1]  
[1] Racah Institute of Physics, The Hebrew University, Jerusalem, Israel
[2] School of Computer Science and Engineering, The Hebrew University, Jerusalem, Israel

Quantum sensing and metrology in the presence of noise have attracted great attention over the last few years. While noise sources with a finite correlation time can be counteracted by refocusing techniques, relaxation (T1) noise cannot be overcome by these methods and thus imposes a fundamental limit on the sensitivity of quantum measurement. It was recently suggested that utilizing quantum error correction in the sensing protocol can provide the ability to overcome this limit. In this talk I will present two examples in which realistic signals can be sensed with precision that exceeds T1 limit thanks to error correction schemes. The First one is a superconducting architecture in which magnetic signal creates two body interaction that can be sensed with error correction. The second example is a combination of photodetection and error correction that provides the ability to sense single body operators.