Multiparameter squeezing for optimal quantum enhancements in sensor networks

Understand

Squeezing currently represents the leading strategy for quantum enhanced precision measurements of a single parameter in a variety of continuous- and discrete-variable settings and technological applications.

• However, many important physical problems including imaging and field sensing require the simultaneous measurement of multiple unknown parameters.
• The development of multiparameter quantum metrology is yet hindered by the intrinsic difficulty in finding saturable sensitivity bounds and feasible estimation strategies.
• Here, we derive the general operational concept of multiparameter squeezing, identifying metrologically useful states and optimal estimation strategies.